Do you not understand what a succubus is?
Her being a a succubus, is the exact reason for her ease and speed in getting sexual.
The headmaster of Cait's college, along with every other magi we've met, has been massively shocked by how much raw power the MC has.
Don't forget, their trap (designed to protect the college against harm from intrusion, so their main defence) couldn't hold him.
He blinked out of it, like it was nothing.
Have to wonder how much concern Rae would have about the Infernals, when she's got the protection of the most powerful magic user around.
She's just a succubus. Not the demon equivalent of James Bond.
Exactly. The MC is even able to override normal rules of traveling through the ether. Notice that, when Cait first asks him if they can leave the cage, he says he can't do it (no pull to tug them back). But when he sees her plead — this innocent, frightened creature to whom the MC has grown incredibly close — he basically (almost certainly subconsciously) forces the ether to obey his will and take them back. Not only could he escape the power of the college, but he also managed to manipulate the laws of magic to force his will. That alone would give anyone with knowledge of how things ought to work a
huge reason for pause, if not extreme concern. I think the heads of the council are very scared.
As for Rae, I believe she's actually, somehow, fallen in love with the MC. She's a being of pure lust and yet somehow finds herself driven by more than sexual urges, something she very well might have never experienced before. I think she has loved people before (like Lady Sirenia), but she's never had this deep of a connection to anyone. I don't think she has any idea what to do about it, but she's come to fully embrace the feeling and fully committed to the MC. It may not be in her to ever become some equivalent of a wife or anything, but I do think she's effectively drowned in an ocean and embraced the feelings washing over her.
ZanithOne