Quick answer — Nekosuke Ookuma worked on The Testament of Sister New Devil DEPARTURES (Original Character Design), The Testament of Sister New Devil: Tojo Basara's Hard, Sweet Daily Life (Original Character Design), The Testament of Sister New Devil BURST: Tojo Basara’s Perfectly Peaceful Daily Life (Original Character Design) and 4 more anime.
Nekosuke Ookuma worked on The Testament of Sister New Devil DEPARTURES (Original Character Design), The Testament of Sister New Devil: Tojo Basara's Hard, Sweet Daily Life (Original Character Design), The Testament of Sister New Devil BURST: Tojo Basara’s Perfectly Peaceful Daily Life (Original Character Design), Shinmai Maou no Testament: BURST Specials (Original Character Design), The Testament of Sister New Devil (Original Character Design), The Testament of Sister New Devil Loli Ero Succubus Maria no Characommentary Tsuki Hizou Eizou (Original Character Design), Hundred (Original Character Design).