Any estimates how many times it may take? I tried around 5 times and she still gets angry when I see her peeing. I got around 400 affection points by now.
Don't remember exactly, but this is what you are supposed to do according to the walkthrough for getting the watersports scene at the bathroom...
51. Go to the bathroom when Janice is in the shower and not using the toilet or Julia is in the tub:
b) "Continue watching": Jason gets caught by Janice spying on her. Janice's score decreases by 5.
After Jason gets caught 4 times, Janice puts him over her knee and spanks him. (Janice repeats this every fourth time she caughts Jason.)
Now go to the bathroom when Janice is using the toilet (between 20:00 and 22:00). Make sure you had sex with Janice at least once. Click on "Peek".
Janice spreads her legs and lets Jason watch her pee. Go back to the bathroom two times when Janice is using the toilet to extend the scene each time.
Then you can choose to pee in her mouth or let Janice pee in Jason's mouth.