Girl. In college, there's a 15-minute rule. Your professor not there... you can leave. Though it may not be an 'official' rule... it's what we lived by.
We waited 30 minutes last time... so TWICE as long as a tenured prof. ๐
And how long can you 'play with yourself'.. until you just give up? ๐คฃ
I usually last longer than that....