God of Fighting from Another World

"Suppose one day, you travel through time and find yourself in a different world. The top killer of the 21st century travels to another world. Faced with his "embarrassing" "current situation", will he choose to "continue"? In his previous life, he was the top killer of the dark world of the 21st century, and in this life, he is the weak heir of a wealthy family. In this magical world of fighting spirit, where should he go!? This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.