Eriko Takeda

Aichlikkwadrou, otherwise known under her pseudonym Eriko Takeda (武田 絵里子 Takeda Eriko), is Takuya Arima's Class 3-C homeroom teacher and school doctor at Sakaimachi Academy.

History
Aichlikkwadrou worked as a scientist alongside Abel (Aichlikkwadrou's lover), researching the Tree of Vrinda and the origins of the parallel worlds. The two created a device that would allow one person's consciousness to travel through the worlds and get a physical view of it. Abel went in, but his mind was corrupted by an Ethereal being, who then attacked Aichlikkwadrou and escaped.

To get revenge, Aichlikkwadrou joined the Dimensional Inspector Bureau, an organization dedicated to tracking down criminals from across all space and time. She dedicated the remainder of her life attempting to track down the being now known as Ryuzoji, who is wanted for wanton destruction across numerous parallel dimensions. Following him to Sakaimachi, she assumed the alias Eriko Takada and worked undercover as a teacher.

Etymology

 * The name Eriko means "picture, painting" (絵) (e), "village" (里) (ri) and "child" (子) (ko).
 * Eriko's surname Takeda means "military, martial" (武) (take) and "field, rice paddy" (田) (ta/da).