
Quick answer — Keiko Kai worked on Kingdom Season 2 (Color Design), Beelzebub (Color Design), Hellsing (Color Design) and 3 more anime.
Keiko Kai worked on Kingdom Season 2 (Color Design), Beelzebub (Color Design), Hellsing (Color Design), Ristorante Paradiso (Color Design), Valvrave the Liberator 2 (Color Design), Blue Seed (Color Design).