Youkoso Jitsuryoku Shijou Shugi no Kyoushitsu e - Volume 15.5, Chapter 6: An Inevitable Past, Part 4

Fate, a gatekeeper who had been working for the castle, is beset by a few burdens.

Talent, appearance, power.

Cultivating his power by slaying demons and taming countless beasts, the emperor solidified his throne as the world's ruler. But not once in his life had he expected that his disciples would use research on demonology to sap the world tree's power and push the world to destruction.Trying to fix his mistake, he opted to use all of his cultivated power to cure the world tree and block anyone from sapping its power ever again. But in exchange, he was to lose all of his power.But...the worst had happened, his wife... had betrayed him.

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