"Hermione," Harry asked, sitting next to her in the Gryffindor common room, "I was wondering, is there any way to personalize a potion, to make it work for an individual only, or to work better for an individual?"

Hermione was startled, as Harry had never shown any interest in independent potions development, and further more, he was very focused on her, awaiting her answer. "Well," she began, "most potions efficacy can be increased for an individual if they are infused with a part of that individual in the initial brewing process."

"A part of the individual? Like blood or something?" Harry replied questioningly.

"Well, yes, but using blood is considered dark, usually hair, tears or other bodily fluids are used," she said clinically, refusing to blush.

It took a moment for Harry to process her answer fully, and when he did, he blanched and looked slightly uncomfortable. "Err…thanks," he said, before quickly retreating to his dorm.

Several Months later

"Hermione," Harry asked, sitting next to her in the Gryffindor common room, "I was wondering, is there any way a potion that is personalized to an individual, that is usually hazardous to consume regularly can be counteracted?"

Hermione looked at her best friend and contemplated what he was asking and whether or not she wanted to know why, in the end she decided she didn't want to know, and answered, "unless you can somehow incorporate a neutralization agent, like a bezoar into the potion successfully, there really isn't."

"Ummm….Ok, thanks," Harry said quickly, his eyes becoming unfocused as he apparently got lost in thoughts of potion mastery. Hermione was still upset that he continued to use the Half-Blood-Prince's notes.

A week later

Harry Potter confidently walked down the stairway from the boy's dorm, dressed in stylish clothing and looking casually elegant, he winked at Hermione, as he sauntered out of the common room.
Something was definitely up with that boy, Hermione thought to herself, and sighed in frustration as she abandoned her homework to go look for Harry to keep him out of trouble. She quickly scrambled out of the portal and was just in time to see a hand reach out from an alcove, grab Harry by his lapel and violently yank him into said alcove.

Suddenly fearing for Harry's wellbeing, Hermione drew her wand and ran down the hallway towards where Harry was ensconced. Before she rounded the corner, she heard a purring female voice whisper "Merlin, Harry, you're huge!"

Hermione rounded the corner and saw Harry leaning against the wall, hands behind his head, eyes closed, while one of the Patil twins kneeled before his disrobed lower body, obviously lost in her own little world as she bobbed her head rapidly up and down Harry's shaft.

"Harry!" Hermione shrieked, "What the bloody hell!"

Harry just opened his eyes, while the Patil girl ignored her completely, "Hi Hermione," he said casually. "Would you believe this was a potions accident?"

Hermione paled, for the first time in her life wondering if she didn't have a little bit of an inner eye, because she knew she wouldn't like his explanation. "Explain, now!" she growled, ignoring his initial response that her growl was a bit sexy.

"Well, it all started with trying to personalize Felix Felicis to be more effective for me, because Merlin knows I have the worst luck. You even helped me with that, remember, you said blood was dark, but other bodily fluids…"

Harry trailed off as Hermione grabbed her head and groaned, while chanting "this isn't happening, this isn't happening…" over and over again. After several dozen repetitions, she managed to marginally get a hold of herself, "so I suppose you figured out how to integrate the bezoar?" she asked rhetorically.

"Yeah," Harry answered enthusiastically, "it was really easy, actually. The only side effect is that, in addition to a significant increase in confidence and luck and a much improved disposition, is well," he pointed to his crotch, where, despite the conversation, what Hermione recognized as Parvati by her tie, continued to suck Harry off.

"Harry," Hermione muttered, "you suck at potions, how did you possibly do all of this?"

He grinned cheekily back at her, "I used the potion Slughorn gave me to figure out how to make more, I used the second batch to figure out how to personalize it, and I used the third batch to figure out how to make it non toxic."

"Bloody Hell," she swore, "Well, you created a whole new potion, Harry, what do you want to name it."

"Felix Fellatio!"