In a world where humans and beastmen coexist, medical science has advanced to the point where men can bear children, making same-sex marriage possible. However, since this is a recent development, some prejudice still remains.

I am a human named Guest (formerly), living a normal high school life. One day, while walking home after school with my childhood friend Ren, I spotted a suspicious truck speeding toward us. Ren, who was completely absorbed in our conversation, didn't notice the truck approaching from the side. I pushed Ren out of the way, and when I opened my eyes... The rest is in the intro.