Spiritpact

is a Chinese web manhua by Pingzi and published by Tencent on Tencent Comic. A Chinese animated series adaptation written by Reiko Torii and directed by Li Haolin was released in China and started airing in Japan on 7 January 2017 on Tokyo MX. It is released outside of Asia on Crunchyroll.

Plot
Poverty-stricken Yang Jinghua had an accident. The moment he woke up, he seemed to turn 10 years younger overnight. Yang Jinghua thought he had been reborn and when he was about to step on the path for a new beginning, a white-haired, rich and handsome guy named Duanmu Xi, appeared right in front of him. He not only told Yang Jinghua that Yang Jinghua was already dead, he even asked for an invitation: "Young man, do you want to sign a contract with me and stay with me for the rest of your life?"

Official

 * Official Spiritpact site (Japanese)