Eh, I don't think anything will happen. Shiina got into a bad mindset and if there was to be any actual assault aside from desperate "pindown" it would happen now, and not have a "cliffhanger" of this sort.
While of course, this isn't good, I gotta say this is a really neat story. To show how society can pressure you into certain things that affect you even when you're "Not entirely" as the society would like you to be. However odd that phrasing sounds. Even if you just look at it from an age gap perspective, worrying over those things isn't that odd. Although, as I said before, I think there's a lot more pressure on poor Shiina. While it doesn't make what she's doing justifiable, I still don't think it'll be an actual assault.
Also, I just noticed but this scene here is how this entire manga started huh.
And I have to say that after that last scene, the trivia page seemed a bit comical in terms of timing. "Anyway, that sexual assault attempt aside, here's some trivia about this place they had their first date."