(Sorry for late reply!)

I wasn't *intending* for there to be any sex, mostly just tickling & teasing until ejaculation, BUT if you feel so inclined to include it if you feel it fits the story you're writing, then go for it! If you include sex, though, I would only do it with the first girl. The person I'm basing girl 2 off of actually has a boyfriend (which you might wanna reference) and girl 3 just wouldn't want to.