Well, I noticed that you live in Europe, and these are U.S. laws quoted. I tried to look up how it is in Europe, but this varies per country and I don't know where you are located.

Still, this person in the U.S. lost their teaching certification.

I still think it's best to err on the side of caution and to avoid the whole thing. There are plenty of other fish in the sea, so to speak, and this one girl doesn't have to be your only choice. You're not stuck on an island with her.