Live, Kiki!

(from ebookjapan):
This human drama depicts the fierce life of Kiki Nakata, aka Kiki, a boy who grew up abused by his mother. Kiki, a boy born in a pigsty, was abandoned by his mother, a drug addict who prostituted herself at home, and was horribly bullied at elementary school. One day, Kiki tries to jump off the roof of a building thinking it would be better to die, but he hears a voice from the sky saying, "Live, Kiki," but then his classmates come along and push him off the roof. ......?