
Quick answer — Kumi Ishii worked on Rozen Maiden: Ouvertüre (Character Design), Rozen Maiden: Dreaming (Character Design), Rozen Maiden (Character Design) and 10 more anime.
Kumi Ishii worked on Rozen Maiden: Ouvertüre (Character Design), Rozen Maiden: Dreaming (Character Design), Rozen Maiden (Character Design), Kurenai (Character Design), RideBack (Animation Director), Dogs: Bullets & Carnage (Character Design), Magic-Kyun! Renaissance (Character Design), Red Garden (Character Design) and 5 more.