It was his first Chunin exam. He did well on the written portion of the exam, but then she jumped in through the window. At first, she was just another teacher, almost completely irrelevant to him. He forgot her entirely the moment he entered the forest, too busy trying to survive. He didn't think about her when he dropped out, either, he just walked away with a cheerful smile. But she followed him out and stopped him in the hall. There's a form you need to sign before you drop out. Follow me, it's in right in here. The room was small and simple, nothing unique about it. He waited for her to give him the form, but he never even saw it. She pushed him to the floor, straddling his hips and holding him down. He tried to hit her, but she easily caught his wrist and restrained him. He opened his mouth to call for help, but she pressed a kunai to his throat. Just lie still and enjoy it. He started to cry, humiliated, as she undid his pants and slid them down to his knees.
He never admitted it. When he saw Orochimaru, he almost told him, but held back. Her words rang in his ears-I saw how much you enjoyed that. For years, he thought she was right. Of course he liked it. A woman couldn't... hurt... a man like that. If he hadn't wanted it, his body wouldn't have reacted the way it did. But no matter what he told himself, he still flinched when women stepped too close to him. He still had nightmares. He still skipped sex scenes in books. And he began to hate himself. He washed his hands constantly, showered every day, cleaned his scalpels obsessively. He made sure everything around him was clean and orderly, a stark contrast to how dirty he felt.
So when she fell down, he smiled. He was stronger than her now, he had won. Before she lost consciousness, he moved to undo her pants, to make her feel filthy and ashamed like him, but he couldn't do it. His hand trembled, and he couldn't touch her, couldn't undress her. Instead, he kicked her as hard as he could, again and again, sobbing. I didn't like it! I didn't! He beat her half to death, cursing her, cursing his body, cursing the goddamn Chunin exams. Finally, when Anko was bloody and broken, Kabuto collapsed next to her, pushing up his glasses to wipe at his eyes. And even though she was dead to the world, her lips formed a mocking half-smile that spoke louder than her words had all those years ago. She was right. No one would ever believe him.