Kyosei Tensei

Story:

"All men are scum, every one of them should be killed!" The curtain rises on the tale of history's worst reincarnation story. After killing the 15 people who raped his girlfriend, Anezaki Satoru was to be sentenced to death, however, he now finds himself in another world. A parallel universe where a solar flare has devastated humanity and melted men's brains so that they are no more than beasts who only think about rape.