: Though her role is minor in this specific episode, she appears as a recurring background character often involved in the school's chaotic events.

: A disciplined student and the daughter of a police officer, her presence adds a new layer of tension as she constantly monitors Nagasumi and Sun.

: The episode introduces Mawari Zenigata , Nagasumi's childhood friend and the strict leader of the school's Disciplinary Committee.

Detailed episode guides and character lists can be found on the My Bride is a Mermaid Wiki and Wikipedia .

: Mawari begins to suspect Sun's true nature after she briefly glimpses Sun's mermaid tail following a water-related accident at school.