Main focus is guro, and there will be no sexual stuff?
Can player at least avoid all of this and brute their path to victory?
There's a couple of sex scenes, but the main focus is certainly on guro. The game is quite difficult (or was, when last I played; I haven't tried the update yet), but victory is definitely possible. A bit of savescumming is advised, though.
That said, I can't recommend the game if you're uncomfortable with guro - not unless you're really,
really into winged giantesses. It can be avoided, but it appears to be one of the primary appeals of the game - you might not find enough other scenes to justify playing it.
(Oh, and to address your earlier question, "guro" generally refers to sexualized death; the most straightforward example I can think of would be someone having sex with a recently decapitated corpse. Or to quote a description I once heard, "It's that serial killer shit". Hard vore and cannibalism are generally considered under its umbrella, in my understanding.)