I walked in to the apartment once just in time to hear his bedroom door slamming and there was porno on the TV hehe. I didn't care though because I had jerked off in the living room myself sometimes. We had our own rooms, but only 1 TV so any video tapes we got could only be watched in the living room. The worst though, was coming home from work to find an open jar of Vaseline next to my playboy collection in my room. I just yelled "What the Fuck?" and flung the jar out into the living room where my roommate was watching TV and slammed the door. We never talked about it but I"m sure he was embarassed. DON'T jerk off in your roomate's room if you have separate ones. That's just plain rude.
The 2 beds in 1 room deal sucks, especially if your bed has squeeky springs. A roommate that snores is very nice for this purpose. Doing it in the bathroom or the shower is preferable, but not particularly comfortable. As others have said, chances are your roommate has the same problem, and will be fairly understanding as long as you're not totally out of control
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