Wo Kai Dongwuyuan Naxie Nian
English title: Those Years I Opened a Zoo
Japanese title: 我开动物园那些年
Type: ONA
Episodes: 13
Source: Novel
Genres: Comedy, Slice of Life
Studios: Haoliners Animation League
Producers: bilibili
Duration: 14 min per ep
Rating: PG-13 - Teens 13 or older

Duan Jiaze inherited a private zoo and was forced to sign a contract after his graduation. And from that day onwards the first ever age classified Luya zoo appeared, those aged under 21 are prohibited to enter.

(Source: Twitter User Xiyoumiyu)