Cthune

Kuuko's distant cousin and a Cthugha, who is sent to Mahiro's residence to supervise her, and has a huge crush on her. Like her cousin, she is an inspector from Plantary Defense Organization.
When Kuuko was little, she tricked her into saying that she wants to marry Kuune sometime in the future, while Kuune recorded it and played it to the whole school.

(Source: ANN)