There's this manga. I cant remember if it's a BL or not, but there's a demon/oni that rules/owns over a bathhouse and either a girl or boy (can't remember) ends up there as part of a debt that their grandfather owed and the girl or boy is supposed to be the owner's wife, but the girl or boy rather work there than get married.
What chapter does she give birth to the snake babies ?
Good thing I save this :v
https://www.mangago.me/read-manga/beauty_and_the_beasts/nbt/mpn_chapter-2283560/pg-1/
This left me feeling so unsatisfied with how things turned out.