Kyosei Tensei is a Manga/Manhwa/Manhua in (English/Raw) language, Adult series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

Anezaki Satoru, a Genius had his childhood friend murdered and r@@ped, he then tracks down her 15 killers and he murder$ them, he then gets sentenced to death for his crimes of murder, after being executed though, he found himself in a parallel apocalyptic world...