I didn't really get in the last chapter why Aida went to the hospital. It's not convincing that he'd be able to just tell that Shiratori is the kind of girl he could easily make infatuated with him . Sure he's considered a popular teacher but coming on so strongly in the hospital is high risk, lots of girls would reject him.
So why did he take the risk? Is he thinking "maybe Shiratori already has a copy of the video of me installing the camera so I have to seduce her ASAP" ? It doesn't seem like it.
I'm glad that Shiratori didn't just become a push over. Her becoming a vengeful jilted lover over Aida toying with her feelings and becoming an adversary is much more interesting.