The Chosen One (Tensura, OC-Masayuki)

My name is Masayuki Honjou, and I'm an Isekai protagonist twice over. In my past life, I was a street orphan named Rudra, who built a crime empire and ruled over Japan's underworld.

I think... I died from a nuclear bomb after starting the Massive Underworld Civil War?

(What happens when Masayuki has the hazy memories of his most unhinged reincarnation.)