Disclaimer: Characters and settings belong to J.K. Rowling. Sue not.
In Seventh Year Gryffindor, there were only two boys left, and Ron was the Head Boy. He got his own room. Harry slept in the same bed he'd had since First Year, in the same dorm, with the absence of prior classmates felt in the night by the lack of Neville's snores, Dean's mumblings, Seamus' restless movements, and Ron's occasional high-pitched whine.
Harry found the sound of his own breathing oppressive. He would lie for many hours, until he was unsure of his wakefulness. Dreams and reality melded with a frightening ease.
It was a winter night the first time he saw his dead Godfather, Sirius Black. The House Elves were good about keeping the fireplaces blazing, yet Harry curled under a mountain of blankets and shivered. Chills seemed to creep into him no matter the amount of heat, and his teeth clattered against themselves. Harry had closed his eyes for a blink, and when he'd opened them Sirius stood before the fireplace, shadowed and somber. Harry thought, I must be dreaming.
This didn't stop him from calling out, "Sirius?" This didn't stop Sirius from coming to him.
Sirius appeared once or twice a week from then on. Things didn't change so much. Harry slept easier, cradled in his Godfather's arms, and on the anniversaries of deaths he had an embrace to unashamedly weep within.
Harry sometimes thought, rebelliously, I don't care if he's a hallucination or dream. He's real enough for me.
Then Sirius kissed him.
It was an unremarkable night save for that fact. A fire was sparking merrily, and the shadows were not so viciously close, and Harry was sleeping against Sirius' chest with a blanket wrapped around them both. Sirius shifted Harry around, and, staring intently at the teen's slack face, took Harry's mouth with his. The press of lips to lips was not erotic: chaste.
Harry's eyes opened.
He looked at the face of his Godfather, so near to his own, and he knew. It was a cold knowing, and it distantly brought a wave of hurt and anger so intense they turned to hatred. Harry said, "Hello Tonks," and watched Sirius' face flush with cherry colour.
Harry broke free of Tonks' grip. He scrabbled off the bed and stood bare foot in his pyjamas on the cold stone floor. "Take off his face."
Sirius' face grimaced, then changed into the familiar heart shaped visage of Nymphadora Tonks, Metamorphmagus Auror. She huddled miserably in the blankets, head ducked in shame. "I'm sorry," she said. "I'm sorry."
"Dumbledore asked you." It wasn't quite a question, and Harry watched Tonks nod. "Why?"
"He thought you-"
"No," Harry shook his head. "I didn't mean that. I know Dumbledore's intentions. Why did you kiss me?"
Tonks shrugged helplessly. "I couldn't not. I don't know why."
Harry watched her for a timeless moment. Then, he said, cold as the floor beneath him, "Get out."
She did. The next night, Sirius was back. Harry hadn't the strength to do it again. He curled in his Godfather's arms, drifting in dreams, and thought, It's real enough for me.
He almost convinced himself.