
kyuu's pouting because he still wants to be carried
http://www.mangago.zone/read-manga/demons_can_t_be_pretty/uu/ibx_chapter-49/pg-18/

i at first thought that the ruler of hell,satan, and the kid,satan, were the same person but it doesn't seem like it
so i'm guess he's a half demon half angel, because of his appearance and immunity to angel weapons.
it was a taboo so his parents begged for his life, in exchange for theirs
it'd make sense if they put him with the angels because of his looks but i'm guessing his dad was the angel and his mom was the demon. dad was executed and mom died in childbirth
angels rejected him because he was "tainted" and wasn't born with wings, and demons took pity on him

that's what i was thinking too
and Gabriel hates Satan with a fucking passion because Gabriel asked God for something really important to him ( since the mom who is a demon would be carrying the child, he probably asked along the line of "let my wife give birth to our child in heaven so i can take care of it when she dies of childbirth so it will not be killed as an abomination" and now he does not know if the child is even alive)
but Satan did not have pity on him by backing down and letting him win (he was probably asking for something for the overall well-being of demons) now Gabriel is being extremely petty by always asking for dumb shit so Satan can't get anything important done
thank you for coming to my TED talk
i released the most intense "yeah" in chapter 4