It'll be fine. The incest part really isn't "incest". (Still kinda ick. Just a little.) It'll make sense when you get there though.
As for the bestiality... Well, in the novel it wasn't really described in detail. Maybe the manga might just glaze over it.
bestiality? Is the ML secretly an animal?
Nah. The beastiality part ain't related to MC, ML, or any of the important characters. They're just audience.
Ohh I wonder why the author included it thanks for letting me know!
Judging from the comments, as fucked up as some things are it's a really good novel. I'm like I can't do incest or beastiality but it peaks my curiosity. Guess I'll dive right in and see how I feel when more manga chapters come out.