when i got to the top of the stairs, i was pushed from behind into a bedroom across from the bathroom. i couldn't see who pushed me. brett and mark came into the bedroom and locked the door behind them. there was music playing in the bedroom. it was turned up louder by either brett or mark once we were in the room. i was pushed onto the bed, and brett got on top of me. he began running his hands over my body and grinding into me. i yelled, hoping that someone downstairs might hear me. both brett and mark were drunkenly laughing during the attack. they seemed to be having a very good time. mark seemed ambivalent at times, urging brett on. and at times telling him to stop. a couple of times, i made eye contact with mark, and thought he might try to help me.