Naruto: I Can Upgrade My Techniques Infinitely - Chapter 15: Young Itachi!

Soul System Online...][Vengeful Spirit Detected]Zero was once a legend a warrior feared and respected across the land, an SSS-ranked hero at the peak of power. But even the strongest are not immune to betrayal. His so-called allies turned against him, casting him into oblivion. Now, he lingers as a vengeful spirit, unable to move on, his legend seemingly forgotten.But fate isn’t done with him yet.When a mysterious boy with the rare ability to see and communicate with spirits crosses his path, Zero sees a chance for revenge and maybe even redemption. Armed with the enigmatic Soul System, he will carve a new path, defying death itself.The world thinks it has seen the last of him. They couldn’t be more wrong.The SSS-Ranked Troublemaker has returned. And this time, nothing will stop him.

It’s said that the prince of virtue had almighty martial arts. It’s said that the prince of virtue had the most handsome appearance in the world. It’s said that the prince of virtue was brilliant. But all was legend! A fire ruined his wonderful appearance and his legs. Even the talented bride under their marriage agreement were replaced furtively. Ye Liu-li was his bad-luck substitutive princess. She went a long way to graduate from Medical University and had her internship with pain and joy. Who knew that in order to save a suicide patient, she fell off the building and crossed time into a “chessman” of prime minister. She had also been married to the disabled prince replacing her elder sister. On the wedding night, when most other couples were having their romantic night, she was thrilled. It didn’t matter. Revenge never came too late. She would never let go of any of them who entrapped her or harmed her.

- Description from Novelupdates

The ordinary world is not ordinary, ordinary people are not ordinary, and safe places are not safe.

This is a story of a passer-by male protagonist who is entangled by various girls with strange hobbies or even non-human beings while surviving in the cracks and opening a harem.

- Description from novelbuddy

The strongest Demon Lord dies, and reincarnates as a human. Not only that, he because of various incidents turns into the hero’s best friend.

Follow his journey as he tries to help the hero escape his fate, and on the sideline to conquer the continent while he’s at it.