ive read in the comments that this is an incest? wtff??? tell me im wrong

Tag above shows "brother" not sure though

No. Its not. I think it's tagged that way bc there are 2 esper brothers who want the same guide. There may be a threesome at some point, but it will be more of a double team than a full "everyone fucks everyone" threesome.

Pretty sure there isn't a threesome, I recall a spoiler giving that info.