
Quick answer — Yuu Amano worked on Problem Children Are Coming From Another World, Aren't They? (Original Character Design), Problem Children Are Coming From Another World, Aren't They? OVA (Original Character Design).
Yuu Amano worked on Problem Children Are Coming From Another World, Aren't They? (Original Character Design), Problem Children Are Coming From Another World, Aren't They? OVA (Original Character Design).