I would be surprised if there is a valid reason that makes sense for both. I've never felt Ripples did the whole "non romance" very well, or at least it doesnt really change anything, imo more an noticeable issue for the girls from 99'
Luna is probably the biggest example. No matter what you did previously (at during the upcoming party if her and MC interact) she still tells her adult daughter to stop seeing her adult friends adult "roommate"

.
Cant really recall instances where skipping a girl offered anything most of the time it just weakens whatever is going on in a narrative sense (skylar).
Also considering that there is a single girl that recognized MC, one of them sort of recognized him after looking at a damn picture of him taken a few days ago (mc perspective), and the rest literally just think they got fucked by some brown hair? there is no way Tiffany remembers a sex scene
If for some reason Jestur 100% needs to reference this line it could just be Tiffany (and possibly others) catching Jenny and MC fucking at the party. That way you dont need the "remember having sex with someone vaguely MC like" and the memory could be "that time my nerdy sister got caught having (insert over the top animation) sex at the party"