So to start this off, the novel is japanese, and is really similar to Cosutte Alien (the main heroine has a similar alien suit) but more dark and mature. Is about a guy that finds this girl with powers (maybe from the space/alien?) fighting a monster on the street/park? They both get out of that situation and the guy finds out the girl is really naive, and they pretty much start fucking (literally on the first 40 mins or less) it also seems like there's evil people going after the girl. The guy introduces the girl to his school, she becomes a student and theres a few scenes where they fuck on class. There also seems to be a nurse that is evil, and that seduces you in a way (maybe even tricks you?) and if you accept it her seduction it could lead to a bad ending. There's also some tentacle scenes, maybe a bit of fighting? I cant remember if the main dude is useless or gains powers. Theres also a puzzle (chess puzzle i think) that if you mess up can also lead to a bad ending. The bad ending itself is that the girl ends up dying. The other important male character is a villain that shows up outside of school to talk to you and he seemed connected to the girl in some way or another. Any idea??
