Pochi-Gokko.

Synopsis

One day, the protagonist Tomoyori decides to end his own life. But that was not the end—as his eyes opened, he found himself in a strange room. Turns out, he's now the pet of a mysterious high school girl. Yes, you heard that right. Interacting with a high school girl? Could this be a gift from the heavens? Or is it divine punishment? (Source: Shueisha, translated)