The Serial Killer Is Reincarnated Into the Another World.

The Serial Killer Is Reincarnated Into the Another World manga, Serial Killer Isekai ni Oritatsu シリアルキラー異世界に降り立つ
A murderer who cannot stop the urge to kill people, even though he wants to stop, receives the death sentence he wants.
His joy is short-lived, as he is reincarnated in another world. The mission entrusted to him by the goddess is to kill 12 reincarnated people using his murderous impulses.
Not all reincarnated people are saints!