Gyakusatsu Happy End: Ao no Shou

Ao Minato killed his abusive stepfather and entered a juvenile reformatory. However, his youngest sister whom he had tried to protect committed suicide, and his older sister Akane has gone missing. Ao, who stumbled upon a weird shrine, wished for the safety of his sister, which is the only hope he has left, and swears to God that he will do anything for that… A new chapter for the blockbuster suspense Massacre Happy Ending.

(Source: Hakusensha, translated)