[Destruction of Konoha] [Multiple Heroines] In the 51st year of Konoha, the Kumogakure Village sent an envoy to Konoha to sign a peace treaty, but they secretly coveted the Byakugan. To escape his caged fate, four-year-old Hyuga Neji took the initiative to contact the Kumogakure envoys and defected from Konoha...

This book is also called "Soman: The Demon King Who Started the Naruto World"

[No system + multiple worlds + no qualifications to become Kamen Rider + multiple heroines + Demon King + OOC apology]

My name is Tokiwa Sougo, but I am not the little devil king, nor the old devil king. I am Tokiwa Sougo who traveled to the world of Naruto. I had no inheritance and felt that my life was over. But when I was just five years old, my complaints were heard by the old devil king, and I got an unexpected inheritance.

Tokiwa Sougo: I'm not a knight, I'm a demon king.