Responses
I only know two. One of them is very dark, ( http://www.mangago.zone/read-manga/yokosu_inu_mekuru_yoru/ ) the other has an art style that makes them look like shota ( http://www.mangago.zone/read-manga/yupiteru_ni_onegai/). Not incest btw, they just have the same hair— sort of like Virus and Trip from DMMD.
http://www.mangago.zone/read-manga/bachi_bachi_kijima_hyougo/
First story in this one. Haven't read all of it yet, might contain more...
Any mangas with one seme and 2 ukes and they have a threesome?