My mom walked in on GTA IV when one guy on the radio was talking about how hot the Statue of Happiness was and would like to give it a "freedom squeeze." She was infurated, and the fact that I was laughing didn't help. So she took it away and threw it out and I am still not allowed to play it anymore.
I was playing ready 2 rumble boxing: round 2 and when the vs screen popped up, my mom noticed Lulu Valentine's erect nipples. I successfully convinced her that I didn't notice. Same game: my stepdad notices Lulu (yeah, she's my favorite) SHAKING her breasts. I almost just stopped playing.
Playing GTAIV I decided to make a quick pitstop at the nearest Honkers for a bit of a private show at which point my girlfriend walks through the door.She's always treated my gaming habits with suspicion and this didn't improve matters.
Cool list. Guess no one would have had anyone walking in on the shower scene intro for Cy Girls unless they bought it. Which you prolly didn't. Lucky you.
Games walked in on..
Mass Effect (you know)
The Darkness (profanity)
Gears of War (torque bow)
GTA IV (everything)
.. the worst offender: Soul Calibur IV.. (no mum im playing as yoda...no its a fighting game honest!)