Tip : try and learn to use the search engine for < tags only > it is really helpful if you have guilty pleasures like that and don't want to expose yourself to the opinion of random people _
My contribution, this one is close enough i think! son in law x father in law. _ (so they are not relared) (but it feels like they are)
https://www.mangago.me/read-manga/the_kang_s_yeesu/
Another day in this fucked up world and I'm also sealing my lips shut but this one kinda fits
https://www.mangago.me/read-manga/mob_for_jack/
Here incest yaoi list -
https://www.mangago.me/home/mangalist/2517320/
For father x son -
https://www.mangago.me/read-manga/not_equal/
Father and son relationship pls? like they regularly have sex its also fine if like its wih the uncle