An Jie Shen Shi
English title: Divine Envoy of the Dark World
Japanese title: 暗界神使
Alternative titles: Agents in Otherworld
Type: ONA
Source: Novel
Episodes: 22
Status: Finished Airing
Aired: Dec 25, 2020 to May 21, 2021
Duration: 23 min per ep
Rating: PG-13 - Teens 13 or older
Studios: Hai An Xian Donghua Gongzuo Shi
Genres: Action, Fantasy

In order to find the missing friend Xiao Yuan, the protagonist, Jiang Yao, sneaked into an abandoned villa to investigate, but was caught by a mysterious black shadow by accident and almost doomed. However, this was only the beginning of his bad luck. Behind the chain of events, Jiang Yao gradually realized that he was following him as a person who "shouldn't exist". The shadowy crisis, the truth about the disappearance of his friends, the hidden organization of the dark world... Behind the bizarre incident, a conspiracy that spans a thousand years has quietly awakened, and the battle between righteous and evil is about to begin. The animation incorporates suspense, adventure, inspiration and other elements, presenting the audience a struggle story of self-improvement and positive energy.

(Source: bilibili, translated)

Based on Huohong Senlin's (火红森林) webnovel of the same title.