Seme is god of mountain can change to snake. He's dying and need and heir to manage the mountain. Uke help seme at edge of his death. Seme Grant him wish for that. Uke ask to heal his grandpa. In exchange of this wish, uke need to be pregnant w his child. PS: he literally pregnant with snake egg
You may feel your favorite manga should be gathered together into distinct categories for your own reference and, now, you can do this with a LIST. After you've created your list or lists, you can proudly recommend them to other manga fans to showcase and share your taste in manga.
Neko ni Naritai Tamagawa-kun