Try animal X. There are not so many shot showing him with bug tummy, but there are morning sickness and delivery scenes. Not omegaverse, he's a hermaphrodite. warning: it's very sad.but it sure has some fluffy moments.
http://www.mangago.me/read-manga/oyasuminasai_no_ato_wa/mf/v01/c006/25/
from here onwards hehe
thank you for your recomendation:) I'll read it now (●'◡'●)ﾉ
Sex Pistols - its further in the story (sorry I can't remember :'()
jappa no amane - uke gives birth
romantic joutou
harami bara
kudan no kuroneko
abarenbo honey - uh omegaverse but implied I think??
wild wind
I always read the manga that he had sex and know that he was pregnant, and next the baby is born. but I haven't see the manga where heis bearing a child inside and his tummy bicome big. Or when he has a morning sick, or aomething like that. all I know is in tadaima okaeri when masaki has hina. Is there anythink else like that???
sorry for my bad english, i'm learning