Hey I think Mom's random scenes are bugged. I got this in the early game:
"Walking through the hallway you notice muffled moaning coming from your mother's room. Her door is cracked shut, and after a few slipped sighs and squeals, there's no mistake she's masturbating. From the sounds of it, she's going at it pretty hard...
Thanks to the serum I gave her, she can't find any relief unless she's in direct contact with me..."
The last line is wrong because I only made her give my character a kiss in the morning, I didn't even get the opportunity to trigger that change yet.