で・る・た！～おねだり天使とひとつ屋根のした～

Yuuki met a beautiful angel once when he was a kid... He works at a vet now, which is owned by Setsuna, his childhood friend. He lives peacefully with his friends, Setsuna, Shizuru, a nurse, and Wakaba, his younger sister.

One day, he meets an angel again... "It's urgent!" Her name is Seles.

According to her, the world is now facing a serious danger, and there is only one way to stop it. She says, "Please believe me... If I and Yuuki have sex, we might be able to create a savior angel..." "What!? Tell us about it more!"