I do hope it's not Kagechika.
We already got his backstory, and he didn't seem like a person that would care for fame or do this.
If it's not him, maybe Kagechika would be the one to catch this creep. The dude is already going around the campus with binoculars to stalk Shiki, it would not surprise me if he sees the guy creeping on his "Shiki" (but the target is actually Akari.)
If they do catch the creep, the company can do a lot of things. Japanese corpos are litigious and they will not be lenient when it comes to these things. Getting sued is one thing but their identity being revealed would make their life a nightmare.