In Different World with Naruto System (WN) - Chapter 15 Duel

The formless ancient world was infested with despicable demons. They hunted and feasted on mankind, keeping the human civilization constantly in a weak and suppressed state.

During the first known year, a magical mountain descended into the world from the realm of the Gods. Carved on this enormous mountain was a message: ‘Heaven Prevails’…

After the Grand Descent, a name that was given to the descending of the mountain, the Three Great Sages made their ways to Mystic Mountain where they learned to harvest what we now call magic, establishing the Mystic Cults and eighty-one sacred shrines to help aid mankind with the cult’s mystic powers against the eternal fight to the death with demons.

- Description from Novelupdates

Science and magic exist side by side in this world.

This is the peak of the science side with a curriculum for espers, Academy City. In this city where 80% of the population are students, the season has finally come when all residents are excited and fidgety!

It’s Christmas Eve.

Amidst the city showing a cheerful hustle and bustle, ordinary boy who can’t keep up with school, Kamijou Touma, also doesn’t intend to miss this event! He was hard at work in his supplementary lessons…

A backward glance from the default misfortune-prone bastard, the silver-haired sister freeloading in his dormitory, Index, in the heart pounding scene different from the usual, activates a new gluton skill!? While Kamijou tries to desperately stop that, Misaka Mikoto taken in by the Christmas Eve atmosphere appears before him.

Having being plagued by same dream for the past six years, Chu Yanshen discovered a little boy who looked just like him out of the blue. It was only then did he, Chu Yanshen, learn that he had been deceived by the little lass six years ago…

- Description from Novelupdates

This novel is also known as The Yun Family's Ninth Child is an Imp!

She was an unprecedented assassin, a trump card deadly agent, but transmigrated through into Ye City’s number one prodigious good-for-nothing young miss.

I am an ugly woman? I will break out from my cocoon into a gorgeous butterfly that will blind your snobbish eyes!

I am useless piece of heap? Lightning in my hands, I will smite you to a well-cooked crisp!

Her greed and lust for money had no end. She is lewd to the core with no bottom in sight, sworn to have love fortunes blossom all around her. However, a certain someone holding a blade in the left hand and a sword in the right hand began cutting those love fortunes one by one!

The person smiled with perked brows, “Little Ninth, it looks like I have to let you become occupied!”

- Description from Novelupdates