Counterattack System appeared when I'm already At The Mahayana Realm - Chapter 12 - : Emperor Zhou’s Visit

After picking up a phone on the streets, Feng Yuchen was sent to the world of High School of the Dead. He, along with 100 people, have to travel through various worlds, fight and solve quests in order to survive.

Whoever dies in that world, would be teleported back to the real world without memories of what happened before and die in an accident one year later.

- Description from Novelupdates

“I’m in desperate need of money to pay Grandmother's medical fee. I will marry Charles instead of Yvonne as soon as I get the money.”

When her sister Yvonne ran away from the wedding, Autumn was forced to pretend to be Yvonne and marry Charles. Her only wish was to get a divorce after a year. Charles is rich and powerful. His name had been linked to innumerable ladies. He had different girlfriends for every day of a year. Neither of them had expected that they would fall in love with each other.

«Bleh.» — Imp. An Imp, a monster known to kill with a grin, a demon of the world, a creature of incredible might! Something that no force in the world can stand against! At least that’s what the Main Character would like himself to be, the reality is very different, however.

Exactly that Imp stumbles along a path of unfortunate fortunes and grows through it, in a world that hates its very existence.

It grows more intelligent, more powerful, simply better at whatever it needs to do. Amongst other things, that includes raising children, killing Soldiers, and carving wooden figurines for money.

One of the top expert killers, tired of endless assassinations and having survived a cruel and suppressed life, decided to escape the world’s strictest assassin organization.