ok so it appears the 0 chapter is like a chaotic trailer for the story which is basically a yaoi isekai with a dumbass prince and our mc with brain damage. there's like a kid and some horse aswell. I tried my best.
Lol, no... I've read the novel. This isn't spoilers because it's basically the beginning of the plot: the brat is actually an adult and he's like one of these really ancient supernatural creatures who were sealed in amulet-like objects and forced to become familiars that can only come out from the amulet by borrowing the user's power, with which they can manifest a physical form. The mc decides to become a user in order to be able to protect himself etc, and summons the ancient being sealed in the sword, but it comes out like a brat and basically useless, because the mc lacks spiritual power and training, but the brat can't get a new user because no one else is compatible, so he's begrudginly forced to stay in the brat form most of the time while the mc starts to train in order to develop enough spiritual power to become able to summon him in either his adult form or his true beast form, so they can kick some butt... And no, there's nothing gross happening between the mc and the familiar in his brat form!
Oh ok thank you!
I'll brb with some info.