The Last Rising Sun (Assassin)

Alek Gusev is a high-level scientific researcher who created one of mankind's greatest inventions. However, as fate would have it, this same creation destroys everything he knew, killing him in the process. Now he has been reincarnated in another world without his memories. What will happen in the new life of our protagonist? Author's note: Multiverse coming soon. Also, this is a slow developing story. Volume 1 is in the process of being remake, but you have the original volume 1 until while.