1.

Spock was always ill at ease on Vulcan, among his father's stoic people. He thinks his parents knew this, and that his father at least expected him to simply tolerate the situation. When he finds himself at Starfleet Academy he discovers that he is no more comfortable on Earth. His mother's people are more expressive than he can tolerate much of the time, and it exhausts him. The realization that he has nowhere to belong bothers him for far longer than he should allow it to.

It is in the aftermath of Nero, when the Enterprise is limping back into the solar system at impulse power with a crew of half-educated cadets, that he looks at his surroundings and finally realizes where home is.

2.

Vulcans do not vomit, but Spock does. He learns this a few hours after bonding with T'Pring at age seven. She is a slight child, engulfed by her ceremonial robes. When the bonding is complete they part ways, and he is secretly glad to not have to look at the pretty face that is so incongruous to the ugliness of her mind. He feels her resentment, her disgust at being joined to a half-breed bastard, and he empties the contents of his small stomach in the back of his mother's garden when no one is looking. He lives with her presence in his mind for fourteen more years.

The bond is broken the day he leaves for Earth. Spock is suddenly alone in his mind once more, and he is not sorry.

3.

Spock insists that the Academy drop the cheating charges against James Kirk almost immediately upon their return to San Francisco. He doesn't do it because Kirk has won him over—which he has. He doesn't do it because he's changed his mind—which he has. He does it because the Federation needs innovative, creative people like Kirk who can use all the tools at their disposal. He does it because as a professor and a senior officer, he needs to set an example of understanding and flexibility. He does it because as a Vulcan, he needs to learn to forgive before grief and rage consume him. Ultimately he gets his way, Jim's field promotion to Captain is upheld, and Pike joins the Admiralty on Earth.

Spock cannot forgive Nero, nor can he look upon the Romulan people with particular kindness, but forgiving Kirk is one small step forward. And it's surprisingly easy.

4.

Unlike full blooded Vulcans, Spock can sneeze if his sinuses are sufficiently irritated. He somehow goes his entire childhood and adolescence without this knowledge. However, on a routine exploration of a new class-M planet he discovers a strange tingling sensation behind his nose. He presses a finger to his cheekbones, puzzled. It shifts to a stinging, almost burning sensation, and his eyes squeeze shut almost involuntarily. His tricorder beeps and he looks down at it blearily, wondering whether he ought to report the strange symptoms to Doctor McCoy when suddenly—it happens. He blinks his watering eyes, surprised. Then he looks back down at the tricorder. It shows an unusually large amount of foreign pollen in the air. Fascinating. He will have to take a sample and see if he can reproduce the effects back in the laboratory. His hybrid physiology—

Jim and Sulu, the only humans in the vicinity, are unacceptably amused and Jim begins to wail about how that's the cutest thing he's ever seen. Spock, in an effort to preserve his dignity, ignores them both.

5.

Spock learns that he is capable of sweating after a routine stopover at Starbase Twelve. Vulcans do not have sweat glands, and being acclimated as he was to intense heat such as was found on the Vulcan homeworld, Spock had never had occasion to be thoroughly overheated. This day, however, he feels warm and lightheaded, and perhaps he ought to go back to the ship soon and meditate when their business is concluded. He never makes it there. To Spock's horror, he faints in a meeting with Admiral Johnson and wakes up in the Enterprise's Sickbay with Doctor McCoy leaning over him. He can hear the Doctor's voice as if from a distance; he has Rigellian flu, with a high grade fever. His tunic is damp and his skin is sticky, and McCoy presses something cold to his face while Kirk sits by his bed and scolds him as if he were a naughty human child.

Upon his release from Sickbay he returns to his quarters and takes a real water shower, scrubbing hard until his skin is raw and leaf-green. He does not know how humans can stand this.

6.

Vulcans do not mate outside of pon farr, so Spock is surprised, at seventeen, to wake up one morning with an erection. He isn't old enough for pon farr, and he is too afraid to tell anyone, even his parents. Especially his parents, in fact. Meditation fixes the problem, as he has reached an age where he can control most of his body's functions. He knows that humans can mate anytime they wish to do so, and quickly assumes that this must be an effect of his human DNA. It takes little mental effort to keep this problem at bay, and it is many years before he thinks about it again.

Nyota cannot know of pon farr, but one evening she quietly laments that they cannot be intimate because of the physiology differences claimed by Vulcan biology textbooks. Spock does not correct her.

7.

Spock does not like his hair. It is perfectly Vulcan hair. Thin, glossy black strands that grow utterly straight. He does not like how shiny it is, and he especially does not like the traditional way it is cut. He experiments with it after leaving Vulcan, but finds that if it gets too long it tickles his ears in a distracting manner. He cuts it back again. It is at the Academy that he gleans from human culture their tendency to be unhappy about their physical appearances. They worry about their hair, the way their mouths look, the freckles on their faces. For Vulcans mental compatibility is paramount and physical characteristics are unimportant. Beyond proper hygiene it is illogical to concern oneself with such things.

Spock spends time in meditation, attempting to rid himself of this human insecurity. After his mother's death, he clings to this human insecurity with a desperation bordering on irrationality.

8.

When new recruits come on board the Enterprise, the Captain likes to say "Please don't touch the Vulcan!" This annoys Spock, while it amuses the rest of the crew to no end. Nyota speculates one day that Kirk does it to reinforce the IDIC. As much as the Federation preaches it, their efforts in educating the human portions of the 'fleet about other cultures are severely lacking. Many humans genuinely do not know that Vulcans avoid touch, and so Kirk is ensuring that his crew gets into the habit of respecting Spock's boundaries. This will also make it more natural for them to comply with boundaries and customs set by new peoples they encounter in their travels. Spock has to admit that it is a surprisingly clever method of introducing the idea.

What surprises him more is being tied to Kirk and McCoy during a mission gone awry, and realizing that he is not bothered at all by their arms pressing against his. Fascinating.

9.

Christmas bothers Spock. It was his mother's favorite holiday, and it was one she had sorely missed. His father hadn't allowed her to celebrate it, although she'd always secretly shared a piece of peppermint candy with Spock on the appropriate day. He'd taken that private little tradition with him when he came to the Academy, having a single peppermint on Christmas morning and knowing that many light years away a lone human woman was doing the same. His first Christmas on the Enterprise is also his first Christmas after her death, the first Christmas that he will be truly alone with his peppermint candy. The humans are breathless with excitement on Christmas Eve, carrying on with parties in the rec rooms and the mess. Spock feels inexplicably isolated among all these people. He stays in his room and viciously represses the loneliness in his heart.

Jim bursts through the door adjoining their quarters at midnight and shoves a mug of cocoa into his hands. There is a peppermint stick in it. Spock knows the sudden pressure constricting his heart is illogical, but he asks Jim to stay for a game of chess anyway.

10.

On the day James Kirk dies, Spock learns that he can cry. The day Jim wakes up, Spock is there waiting. He cannot explain, does not wish to explain, his emotional failure regarding the Captain. He cannot explain why he did not cry for his mother, his homeworld or the ten billion people who died when Vulcan was destroyed. But for this one man, whom he had known for less than a year, he had shed real tears. What was so different, so special about Jim? Spock meditates that night until his back hurts and his legs are numb. He gets up with the sun and returns to the hospital, where he finds Kirk sleeping with McCoy curled halfway onto the foot of the bed, snoring softly. And then he knows.

It isn't Jim, it's Spock. Spock is different. These two humans pressed together on the hard hospital bed have transformed him into someone else entirely than the young Commander who had watched Vulcan implode. Oddly, he doesn't resent that.

11.

Spock tells his first lie when he is nine years old. His father asks him where the cut on his face had come from, and Spock smoothly tells him that he had tripped and fallen in the arboretum at school. Sarek takes him at his word, blankly dismissing him with an admonishment about conquering his human clumsiness. Spock works hard to be more graceful. He also works hard to hide the marks left upon him by the other children. Spock knows it is wrong to lie, but the preservation of his pride is sufficient reason, he tells himself. He would rather his father think him clumsy than weak.

Many years later one of his fellow professors at the Academy compliments him on his catlike grace. Spock lies easily, and tells her that he comes by it naturally because of his Vulcan heritage.

12.

Spock doesn't need a phaser to kill a man. He is three times as strong as a human, with three times the muscle and bone density. He could crush a human's skull as easily as Khan crushed Admiral Marcus's, but he doesn't need that either. It isn't well known among humans that touch-telepathy is just as powerful and can be just as dangerous as any other form of mental skill. As he tightens his hands around Khan's throat, Spock knows it would be so easy to brush his fingers across those nearby meld points, to shut off Khan's will to live. To trap him in an existence of excruciating pain or permanent emotional anguish.

So easy. Too easy, in fact. Jim is dead, and some dark animal part of Spock wants Khan to suffer as much as possible. Instead he pulls away, and hits the man again.

13.

Space is cold, and so is Spock. He spends most work days in areas held at normal human room temperature, which is uncomfortably cool by Vulcan standards. He wears regulation thermals under his clothes and tries to spend as much time as he can on his feet, to keep his circulation strong. At night he curls up in his much warmer quarters, wrapped in a sleep robe and thick blankets. The humans don't take notice. He knows that although there are exceptions, on the surface they tend to be self-absorbed and unobservant. He is surprised, therefore, when he meets Jim and McCoy one evening for dinner (a "floor picnic," Jim says) to find the temperature in the Captain's quarters significantly warmer than human preferences.

Jim waves him in happily and ushers him to a red and white checked blanket in the middle of the floor. McCoy hands him a plate of potato salad and carrot sticks. Spock sits down, and isn't cold.

14.

Vulcans do not dream, and neither does Spock. But somehow, in the darkness of ship's night, he sees a small human woman falling from a cliff. The faces of jeering children, all sharp chins and pointed ears. His father, nearly sneering at human emotionalism. Jim, pale and trembling behind the glass of the warp core. When this happens Spock gets up, dresses calmly and walks the silent halls of the ship. He is seated on a low couch on the observation deck one night, watching the stars pass by at warp speed, when Doctor McCoy enters. The man is still wearing pajamas, carrying a bottle of some no doubt illicit blue liquid. He sits next to Spock without making eye contact, and says, "Cain't sleep?" Spock tilts his head forward, silent. "Me neither," says McCoy. "Keep seein' Jim in a body bag again."

Spock says nothing, but McCoy does not seem to expect a response. He leans against the arm of the couch, facing the mammoth window. They sit together in companionable silence as the stars streak by.

15.

Vulcans do not celebrate birthdays. So when, on the thirtieth anniversary of his birth, Spock enters the bridge to find the Alpha shift crew singing to him, it 'throws him for a loop,' as the humans might say.

"Happy birthday, Spock!" grins Nyota, handing him a cupcake. Sulu and Checkov continue singing. Scott hands him a card, which so many crew members have written on that there is hardly any space left. Even the envelope is covered in signatures and tiny smiley faces.

"I do not understand the logic of this celebration." Spock says, with as much self-respect as he can muster while holding a pink cupcake and being sung at.

McCoy and Scott roll their eyes, but Jim quickly says, "We are celebrating because we're happy you were born, Spock."

Spock scoffs at their human sentimentality, but when he returns to his quarters at the end of the shift he carefully stands the card up on his bookshelf where it can easily be seen from the rest of the room.

16.

Spock likes tribbles. Unfortunately, the humans are unusually observant and they pick up on this very quickly. Spock comes to his quarters at the end of his shift to find the place swarming with tiny fluff balls, happily trilling away.

Spock does not have to wonder who is responsible.

The next morning Jim yelps when he sits in the command chair, jumping back up hastily. Spock watches with mild interest as Jim scoops an armful of tribbles up out of the seat, looking around with wide eyes and taking in the tribbles that cover every surface of the bridge. The seats, the walls, the databanks, the safety rails. The officers.

"Iz there problem, Keptain?" Checkov asks. There is a tribble cooing on his shoulder.

"Uh, no, Mr. Checkov. No problem." Jim looks directly at Spock, who merely raises a placid eyebrow and turns back to the tribble-covered surface of the science station.

When he returns to his quarters all the tribbles are gone, save one, which has a printed note stuck to it saying that it's been "fixed." Spock feeds it dry oatmeal and lets it sleep on his pillow.

17.

Human medications are rough on Spock's stomach, and Vulcan ones have no effect at all. He never tells anyone this; his mental disciplines allow him to function normally in spite of most discomfort. Until he came on board the Enterprise, this had been sufficient. Leonard McCoy, however, is a uniquely intelligent and stubborn human. He deduces quickly that Spock is still in pain after being shot with an antique firearm, and refuses to release his patient from sickbay until he allows the doctor to do something about it. "You got rules about your mind voodoo, I got rules about my medicine," he says, and pulls something out of the synthesizer. It turns out to be an opiate that went out of fashion many centuries ago on Earth. Spock mentally rolls his eyes, but humors the well-meaning human and allows himself to be drugged.

He wakes up disoriented many hours later on the same biobed, with no nausea and no pain. McCoy howls with laughter when Jim comes to visit and Spock pats his golden head fondly.

18.

Spock does not like children. He was tested as a teenager and informed that due to his hybrid physiology he would never produce offspring, and that is just fine with him. Children are noisy, messy, illogical creatures. His parents had been most displeased, but by that time Spock had accustomed himself to how often they were disappointed with him. Fortunately, he never needs to actively avoid children, because he never finds himself in a situation where there will be any. Unfortunately, this changes on a shore leave at Deneva when Jim insists that Spock and McCoy accompany him to visit his brother's family. There is a ginger-haired child there called Peter, who is immediately fascinated by Spock's exotic appearance.

When the child tugs at his sleeve, staring up at him with Jim's sky-bright eyes, and asks him to play chess, Spock finds that he cannot refuse. He does not like children, but he tells himself that he will tolerate this one for the Captain's sake.

19.

Spock is not in love with Nyota Uhura. He knows this, and she knows it too. He does not think of their relationship as a kind of friendship until after he acknowledges that Jim and Doctor McCoy are his friends as well. Having thus re-categorized his feelings for her, they go their separate ways romantically but in truth nothing in their day-to-day habits changes. The continue to eat together, they continue their research into ancient languages together, and Spock continues to be more comfortable with casual physical contact from her than with most other humans. Nyota has a romantic encounter with Lieutenant Scott, saying that she has fallen in love with his accent. Knowing her as he does, Spock finds this plausible. Spock, on the other hand, seeks no new romance and is content to spend his free time studying with Nyota or chatting over a game of chess with Jim.

On a shore leave at Risa some months later, Nyota coerces Spock into joining her at a gay bar. Spock learns something new about himself very quickly that night, and the surprise must show in his eyes because Nyota pats his arm and smiles knowingly into her drink.

20.

Spock firmly believes in the Temporal Prime Directive. He knows that even if he and Jim understand that their futures are not set in stone, the mere fact of having information they did not have before might alter their decisions. Spock feels guilty and hypocritical when he asks about Khan, but is glad for whatever his elder counterpart is willing to tell him. The Ambassador visits the Enterprise frequently when he travels, as Starfleet expects Jim and Spock to keep an eye on the new colony. They introduce the old man to McCoy as their "time travel expert" and the four spend many evenings chatting amicably. During one such visit, McCoy falls asleep sitting up on a couch in the observation deck. Spock raises an eyebrow at the impropriety, but Jim explains that McCoy has been working a lot of hours and has been very tired lately. When Jim falls asleep next to the doctor an hour later Spock does not raise an eyebrow, because this is typical. The Ambassador pulls a strangely designed tricorder out of his ever-present satchel—no doubt one that he brought with him from the Prime universe—and points it at McCoy. Silver eyebrows knit together as he reads the display, but he says nothing and simply shakes the two awake and sends them to bed. Before the old man beams over to his destination the next day, he presses a data chip into Spock's hand.

Two months later, a paler and thinner McCoy enters Spock's lab to say that he can no longer function at full capacity, but begs him not to tell Jim yet. Spock does not feel guilty at all when he opens a drawer and hands the gaping man a hypospray containing the cure for xenopolycythemia.