one piece: gene extraction and fusion system - Chapter 324: Rise of the Black Emperor

In the world of One Punch Man, the seventh S-class hero of the Hero Association, the King Engine King has obtained the super god skill system.

As long as you have reputation, you can extract the skills of the heavens and the world!

DNF’s extreme swordsmanship, the flames of fire in the god of death, the Tensei and Samsara in Hokage, the top three-color domineering in Pirates, the dragon slaying magic in Fairy Tail… Look at the system panel. For the 100 million prestige balance, KING took a discount and chose Stud. “Ding!”

- Description from novelbuddy

Summoning ceremonies can freely call forth even “those which lurk in the depths beyond the gods”. One boy has top-level abilities even among the cutting-edge summoners who can use those ceremonies. He is Alice (with) Rabbit aka Shiroyama Kyousuke. But this strongest boy summoner has a single fatal weakness. Certain “cursed words” spoken by girls: “Help me.”

When Kyousuke hears those words from Meinokawa Higan, a girl brought to the verge of death, he throws himself into a city where three great summoner forces clash!

Su Xiao is a cold-blooded teenager who’s seeking vengeance for the death of his family, yet things ended up badly for him.

As he was taking his last breaths, he heard a voice calling him from dimensions, it was a strange system reaching him, asking him if he wanted to be saved, to be Reincarnated.

He just needed to accept a contract, Su Xiao didn’t have any choice but to do so, but he didn’t know what he signed up for!!

Traveling through worlds, doing extremely dangerous missions, collecting special items, leveling up, and even killing Protagonists…

But Su Xiao wasn’t any ordinary Contractor, Su Xiao was a Hunter!

The MC crosses over to: One Piece, Tokyo Ghoul, Naruto, Fullmetal Alchemist, Attack on Titans…

- Description from Novelupdates

Only a pure maiden can have a privilege to make contract with a spirit.

In Areishia Acadamy, maidens from noble family were gathered there, giving them an elite education to become a spirit contractor. A boy Kamito, by accident he peeped on a girl, Clair, who was taking a bath, and he even made a contract with spirit that she wanted.

Kamito was actually an irregular male spirit contractor, which should not exist.