Start with the Mangekyo Sharingan: Follow Lord Madara out of Konoha - Chapter 223 - 116: Maboroshi the Great Serpent

Mercenary King Qin Chuan returns back to the city and is arranged by his finance to work as a security guard in the super department store.

Accidentally he is drawn into the struggle with the department store.

What is mine don’t touch, what is not mine you also put it down for me!

After three years continues the legend of the security guard. Watch how the little security guard dominate the city~

Temporary every day 9-11pm, morning 9 evening 5, weekends midnight.

- Description from Novelupdates

Instead of causing chaos with my knowledge of the original work, I assisted the protagonist.

I successfully completed the story and now planned to retire and live peacefully.

However, it seems the protagonist still needs my help.

An academy professor? That’s nothing much.

But why is the state of the academy so strange?”

The heavens have died.The gods have fallen.And the most primal energy—Prana—has vanished, reducing the mightiest god to nothing more than a powerful mortal.And who caused all of this?None other than the God of Destruction himself.---------------------------------------------------[previous name: SSS Rank: Creation Power]Hmm... I think if I say anything more, it’ll be a spoiler. So just go read it—you’re gonna love it.Trust me, I know from the source.

One day, Zhang Fan, a poor medical student, receives a medical system from the future. This turns him into a new shining star in the medical field. Along the way, he must face medical corruption, competition, and infighting from other doctors, and even find time for a love life as he strives for the top of the medical field!

- Description from Novelupdates