Hermione

While all other options were very interesting, it never was going to be anyone else then Hermione, wasn't it. She had been his best friend for four years, and since last year she had really started to come into her body. Feeling her breasts pushing into his back last year, while they were riding Buckbeak, really drove the fact home that his best friend was a girl and a beautiful one at that. It would only be a matter of time before others would start to notice that too, and Harry wouldn't have that.

That leaves only the question of how to get his name on her. He couldn't just walk up to her and write it on her. Then suddenly and idea hit him. He quickly checked his lesson roster and saw that he was free, while Hermione had runes. With a quick couple of shortcuts he made his way up to the common room, going up to his dorm. He opened up his trunk and pulled out a cat collar. It was one of the spare collars for crookshanks. Not that it did any good, he kept pulling them off anyway. But Hermione didn't have anymore room in her trunk and had asked if he could store it away. Placing the collar on his bed, transfiguring it into a black choker large enough for a person. Most importantly on the inside it had written "Harry Potter". He hoped that getting Hermione to wear the choker would be enough to activate this weird gift he had been given.

He stored the collar away for now, planning to get her to wear it this evening