I'm curious about where this will go - while the MC can seen (quite) bizarre, the fact that we are accesssing his (quite) unfiltered comments, thoughts, along with dreams and bouts of reverie do play a role on this. I see a teenager, somewhat sheltered & socially awkward, uncertain of himself and with overactive hormone-laden imagination.
While a number of bits (game title, his name & etc) can lead one to think of the MC as "young porn-oriented Norman Bates", it could be red herrings just as well - we are seeing a family move into a new home into the middle of nowhere, that's a classic horror victim cast setup right there - and MC's "weirdness" a distraction from the real horrors to come in future installments.
Yes, his decision to keep the "savage princess" hidden is questionable at best, but he just found her out and nearly got trounced for that in the process. Calling in other people might cause her to bolt & disappear or worse. For now, i'll give the kid the benefit of doubt.
And as others have said, even if he goes full "animal trainer scumbag" on her, it's not like characters as bad or worse can't be found in a number of adult media. Good, evil or just playing weird, things are looking interesting so far to me.