A/N: This question was posed by Valkyrie-ShapeShifter666. I decided it would make a good one-shot, so I went with it. It's not great but there is a little surprise for you all at the end. Also the dates are probably wrong; I didn't do any fact checking but just assume that they are all 18/19 years old.

Shout-out to TeamJemCarstairs for giving me the correct ID year! XD

Disclaimer: All character in this story belong to Cassandra Clare.

"Hey Clary?"

"Yeah Jace?"

"Is there a rune for portaling to say…another time?"

Alec looked up from the book he was reading. "Don't go there Jace," he said. "Magnus says that messing with the space-time continuum can have dire consequences."

"Oh Magnus –Shmagnus. He just says that because he can't travel through time but wishes he could" Jace replied in a nonchalant manner. "Besides, I was asking Clary. Clary?"

"I think Alec is right," Clary answered. "All the movies I've see where…"

"There you go with those movies again. Movies are fake. Live a little, Clary."

"Well…" Clary looked to Alec for help.

Alec cleared his throat uncomfortably. As much as he knew Magnus was right, he was still curious himself. "What…exactly… were you thinking about doing?"

"Going to the future to see how our lives turn out, or maybe going to the past to warn ourselves about Valentine and Sebastian… That slimy little no-good sack of…"

"JACE!" Clary and Alec shouted at the same time.

"Sorry."

"It does you no good to dwell on the past. Besides, if we surprised our past selves, we could get spooked and kill our present selves. However, our future selves will probably have seen stranger things and give us the benefit of the doubt," Alec stated very matter-of-factly.

"So…" Clary began, unsure of what was going on. "Are we gonna do this or what?"

Alec and Jace exchanged an excited look and Jace said, "let's do it!"

"OK." Clary got up from the desk and moved around to the back of one of the book shelves in the library so she could have a large flat surface to work with. "No promises." She closed her eyes and began searching for a rune that could do what they were asking. She tried to focus on time travel and meeting their future selves, a funny set of swirls and lines came up before her and she began to draw. It didn't look quite right but she had learned not to doubt herself in the past three years since she had learned of the shadow world.

Clary stepped back to admire her work just as the lines began to swirl in a sort of vortex, creating a shimmering pool of swirly blues and silvers. Jace and Alec looked on in awe.

Suddenly, two black dots appeared near the center. They grew bigger and bigger. Clary, Alec, and Jace stepped back as two figures flew out of the portal, landing in a heap on the floor.

"I don't think that was supposed to happen." Said Jace.

"Um…" was all Clary could reply.

Just then, the library doors flew open and Isabelle came storming in. "What was all that racket? Can't a girl get ready for a date without… Who are they, and where did they come from?"

Isabelle came up to join the other three. Alec checked the pulses of the two bodies. "They're alive," he said as they started to grunt and move.

"Get off me, you moron," said the bottom of the two in a rather haughty English accent.

"I'd love to," said the other, also with an English accent, "but I'm having a bit of trouble moving."

"No you aren't you're just enjoying having me pinned." He gave a large shove and pushed the boy off of him.

All the others could do was stare.

The two boys realized they were not alone. They turned and took up a fighting stance.

"Who are you?" asked the haughty boy. They both looked to be about 18 and were dressed in a Victorian fashion. The one that had been on top of the pile had Black hair and blue eyes. The more conceited one had brown hair and green eyes. Both looked slightly familiar.

Alec spoke first. "Well…um… I'm Alec…Lightwood… and this is my sister Isabelle."

"I'm Jace Lightwood."

"Great. I'm surrounded by Lightwoods," said the black-haired boy.

The other laughed. "I am Gabriel Lightwood," he said puffing out his chest rather pompously.

"How did we get here?" asked the boy whose name they still didn't know.

"Um… that would be my fault… I'm Clary…Fray… and I sorta tried to make a portal to the future, but it seems to have backfired a little. This is the year 2015 and we're in New York City"

"Enchanté," the black haired boy took her hand and kissed it. "I'm William Herondale," he said with a wink. "We're from 1878."

"Of course you are," Clary said a little under her breath.

"Wait," said Alec. "William Herondale as in Will Herondale from London?"

"The one and only," said Will. Clary could see the similarities now.

"Excuse me." Alec left the library.

"Are you going to let go of my girlfriend's hand any time soon? Or do I have to cut off your arm?" Jace looked at him a little impatiently.

"Now Jace, he is your ancestor. Be nice."

"Ancestor?" asked Will. "I thought…"

"I was adopted by the Lightwoods, but I was born a Herondale."

"Well," exclaimed Gabriel, "It's nice to see that our family still does a little charity work from time to time."

"What?" asked Jace. At the same time Will rounded on Gabriel. "You want to try rephrasing that statement?" he asked.

"Oh come now Will. Our family is better off than yours now, I'm sure it will be in the future as well."

Will was about to punch Gabriel but Jace grabbed him. "Wait."

"Can I say something?" Isabelle spoke up for the first time.

"Certainly," said Gabriel.

"First of all, I have a date I should be getting ready for so I gotta make this quick. Second, Gabriel, it's not like that. His father died before he was born, his mother died at birth. The man who raised him faked his death when Jace was 10. He was sent here to live with us and has been here ever since. Third, shouldn't we be finding a way to send them home? Just saying." Isabelle checked her watch. "Ooh. Gotta run… Clary, let me know how this turns out, K?"

"OK. Have fun."

Isabelle winked.

Will turned to Jace, "Did she say 'faked'?"

Jace cleared his throat. "Uh, yeah. Turned out he was Clary's father, who was an evil man who tried to 'clense' the shadowhunters and rid the world of all downworlders, not just demons."

"Hmm. Interesting political view," said Gabriel. "Very interesting."

"You sound as if you're actually thinking about it." Will looked ready to punch Gabriel again.

"Just thinking. Don't worry, you and I both know I could never pull off something that big. You're little girlfriend is safe," Gabriel sneered.

This time Will did hit Gabriel. Gabriel retaliated hit a punch of his own and the two set off wrestling and fighting around the library.

The library doors opened again as Jace was trying to separate the two. Magnus strode in with Alec behind.

"Boys. Boys!" Magnus snapped his fingers and the two flew apart. "There is no need to be fighting. Hello Will. It's been awhile." Magnus turned to Will.

"I just saw you yesterday," Will said.

"Yes, well for me it's been well over 50 years."

"So this is him then?" asked Alec.

"Yes Alec. This is the Will I told you about. And as you can see he is as straight as a board, and I am over it. Do you feel better now? Though I am glad you brought me here for this. Now, who is going to tell me exactly what happened?"

"Hold on a minute," said Gabriel, who was catching up to the conversation. "You," he pointed to Alec, "and You?" he moved to Magnus. "You're…you…um…?"

"The term is gay, and yes. We've been together about two years now."

"Oh my God. I can't believe I am hearing this. First my family adopts a Herondale, now one of my descendants is …gay? What next? Are you going to tell me you are all bosom buddies?" Gabriel looked from Jace to Alec to Magnus with a look of incredulity.

"Oh it's worse than that," said Jace. "We're parabatai." Jace went over and put his arm aroung Alec's shoulder, just to prove his prove his point.

If possible, Gabriel's face became more incredulous. "I…but…he…and…you… and…?"

"Easy there Gabe. Don't have a heart attack," said Will. Sheer delight was evident all over his face. "What's wrong? Are you saying the Herondales aren't good enough to be friends with the Lightwoods?"

Gabriel regained some composure. "Yes. I am. The Herondales are nothing but a charity case. No good beggars looking for handouts. They can't even seem to keep a set of parents alive long enough to …"

This time it was Jace who threw the first punch. Will joined him. Gabriel managed to hold them off long enough for Alec to get a hold of Will, and Clary and Magnus to get a hold of Jace.

"So about that explanation?" asked Magnus when they had finally managed to force everyone into chairs on opposite sides of the library table.

Jace looked down and toyed with the hem of his shirt like a child in the principal's office. "It's kinda my fault. I wanted to know if there was a rune that could take us to the future to meet our future selves…"

Alec, who was shuffling his feet while staring at the ground, said, "And I thought it would be cool."

Clary pretended to be engrossed with the goings on outside the window. "And I came up with a rune and drew it on the back of that case." She looked up just long enough to point to the bookcase.

Magnus went over to inspect it. "Hmmm…"

When he came back around he looked a little miffed. "Well, I feel a little lesson on the space-time continuum is in order. First of all, when you mess with time, things tend to get a little screwy. You can kill a grandparent and never exist. You can become your own grandfather, trust me, I've see the repercussions of that, it's not pretty. Let's just say there is a strait-jacket involved. You can change the outcomes of major historic events just by dropping a piece of paper in the wrong wastebasket. Small events cause ripples in time. Ripples grow bigger and bigger. So far you don't seem to have knocked the universe too out of balance so we should send these two back before anything major does happen. Also, Clary, from now on, if you decide to create any portals, can you please make sure I'm present?"

"Yes, Magnus."

"Good, let's get to work. Clary, I need you to retrace the rune you drew earlier. Will, Gabriel, stand beside her and as soon as the portal is fully open, I need you to jump in and imagine exactly what you were doing before you got pulled through so it will drop you off at the same point in time."

Clary redrew her rune, and again it swirled into a pool of blue and silver. "Now," said Magnus. Will and Gabriel jumped through.

When the portal closed, everyone looked around to make sure they were all still there and that nothing was different.

"Well kiddos," said Magnus, "I think we dodged a bullet there."

He was answered by a chorus of exhaled breaths and phews.

"Back to life as usual, and no more portals."

"Hey babe, are we still on for tonight?" Alec asked.

"Yeah let me go grab my jacket." Clary answered.

"Speaking of jackets, sweetie, you left yours at my place," said Magnus.

"All the more reason to come back tonight my sparkly sugar daddy." Jace answered.