Who wants me to take off Snivelly's pants?" James asked. Harry felt sick. If he could have, he would have hit James.
"Put him down NOW!" someone shouted. Everyone turned and saw McGonnagle coming down the lawn. James immediately complied. "How DARE you treat a fellow student like that!" Her lips were as thin as a paper's edge. "I NEVER thought I'd see a Gryffindor act like that! All four of you come with me to my office."
James, Sirius, Peter, and Snape followed her into the castle, Harry trailing behind. When they got to McGonnagle's office, she turned to the Marauders and said, "For all three of you, I think a week's worth of detentions are in order. Now, would anyone care to explain what that was all about?"
"It was their fault! I didn't do anything to them!" Snape said.
"Is that true?" McGonnagle asked.
"Yes, ma'am," the three Marauders mumbled to their feet.
"In that case, I take fifty points from Gryffindore. You are dismissed," she said, glowering at them. They all filed out of her office.
"We'll get you for this, Snivellus," James said to Snape out of the corner of his mouth as the Marauders passed. Snape glared at them. Harry glared at them, too. Then, Snape started down the hall, and Harry followed. They went down to the dungeons. Snape passed the Slytherin common room and went down the hall that, in twenty years, he would teach potions down. He went to the very end of the hall. 'Where's he going?' Harry wondered as he followed. Snape went to what appeared to be just blank wall. He pushed on the stone, and it opened up into a door. They went in and Harry saw it was a half-finished dungeon. Snape sat down on the roughly hewn floor and started to cry. "Damn it, I HATE them! Why can't they just leave me alone?" He yelled at stone walls. He stayed there for a little while longer until dinner was almost over. Then, he got up and went to dinner.
When he and Harry got there, the hall was mostly empty. Snape ate a hurried dinner. Everyone that was in the hall was laughing and pointing at him. Harry was disgusted. How could they have thought it was funny? He invisibly glared around at everyone while Snape ate. When he was finished, they left.
The Great Hall was empty when they went out into it. Snape started back towards the dungeons. Suddenly, there was the sound of someone hitting something. Snape gave a startled cry and fell to the ground. There was the sound of a bodiless voice saying, "Stupefy!" and everything went black. The Marauders had knocked Snape unconscious.

When a room rematerialized, they were in the Shrieking Shack. Harry was standing beside the bed. Snape was lying on the bed. James, Sirius, and Peter were standing over him. "Hello, Snivellus, have a good dinner?" James asked maliciously.
"What am I doing here?" Snape asked. He obviously already knew about Lupin.
"Well, Snivellus, we, that is to say, Wormtail, Padfoot and I, brought you here. You see, we need to get you back for getting us into trouble."
"W-what are you going t-to do?" Snape asked with fear in his voice.
"Well, first, we're going to rip off all of your clothes. Then, we're going to take off our pants. And then, Snivellus, my friends are going to hold you down, and each one of us will have our way with you," James answered. Harry's jaw dropped in shock. No. This hadn't happened. It COULN'T have.
"No, please, DON'T. I swear, I'll never do anything again, I swear!" Snape begged.
"Sorry, Snivellus, but it's like we said this afternoon. Just by existing you get in our way. We have to pay you back," Sirius said in a sly voice. Then, before Snape could react, him and Peter rushed forward and pushed him down. 'I don't want to see this,' Harry thought, but he was glued to the spot. He wanted to leave, but he couldn't look away.
True to their words, the Marauders ripped off Snape's clothes. Sirius and Peter held Snape down while James took off his own clothes. The other two forced Snape onto his back while James walked forward. Harry couldn't watch any more. He wrenched his eyes up and away. He went swirling through darkness and fell, to his horror, at present-day Snape's feet.
"Harry, why did you have to snoop? Why couldn't you just stay away? I don't enjoy entering your mind, and I respect your privacy. Why can't I trust you to do the same?" Snape asked in a broken voice. He sank to the floor and started crying. Of all the reactions Harry expected, this was the last, and by far the WORST, one. Shouting at him would have been a mole of times better. Harry felt lower than flobberworms at the moment.
"I-I'm sorry," he said lamely to the floor. "I shouldn't have invaded your privacy. I-I don't have an excuse."
"Why couldn't they have just left me alone? I didn't do anything to them," Snape said. He continued to cry.
"Did they ever get caught?" Harry asked.
"No. ALL THREE of them raped me. Then, they told me it was my fault for getting them into trouble. I never told anyone because I was afraid they wouldn't believe me, or they would also tell me it was my fault. Then, those three would punish me for telling someone. No, they were never caught," Snape answered.
"You should tell Dumbledore," Harry said immediately.
"No," Snape said. "And you won't tell anyone, either."
"O-of course not," Harry said. He left Snape's office. All he could think about was getting a talk with Sirius.