Glad you already love it! It's still very much a work in progress - tons more to implement, including animations and more comprehensive sounds.
That castle is mostly a placeholder right now (as you can tell by the crash that occurs because I haven't finished building out what happens there) - but what it represents, ultimately, is the game's first objective, including likely the encounter that will be the first boss fight. In the next version, I'll put a placeholder up there so you get that instead of a crash. In the final game, along the way there will be optional towns and dungeons, and then more beyond.
Food is an entire mechanic - basically it's the thing keeping you moving forward, so it will be a bit hard to come by and making sacrifices or overcoming challenges to get it will be pretty common.
As for knowledge of anatomy, and more broadly knowledge in general, that will help in both combat and in interactions - sometimes, knowledge of what lies beneath a wereslut's skirt is all that will keep you from a knotty, knotty end.