Plausible excuses for when your roommate catches you rubbing one out:
"I have lower back tension; what you heard was a very strong back massager. Nah, I'll wait until you leave to use it again. It's so loud and annoying."
"This is the living room? I could have sworn I was in my bed."
"The doctor said I should check for lumps or irregularities."
"Don't worry, this isn't what it looks like, I just pissed my pants, that's all."
"My dick itched. A lot."
"Is this the kitchen? I could have sworn I was in the living room."
At 6:28, "Oh, hey, I thought your class got out at 6:30."
"BACK AWAY, I'M FIGHTING CRIME!!!"
"I just found it in my pants and I wanted to make sure it was mine."
"My hand feels like a vagina."
"Oh no i didn't realize this was a picture of your mom."
"Shit, I didn't know you were in this class."
"Is this your bedroom? I could have sworn it was the kitchen."
"You're just so cute when you're asleep."
"No one will have sexual intercourse with me."