I remember the novel having all types of monster including zombies and there were these really powerful mosnters and the MC got stuck with one (insect type) cause it wanted to feed him to the newborns but he had to fight and trick the newborns to barely escape. He also fused with the insect type and got their wings later on. Last I remember was him fighting together with a girl against a lich lord or smth and the girl got injured/died. Thanks for the help