Dayoonira

Dayoonira is a secondary character of My Best Friend Marneao. She is Amy's twin sister.

Story
Amy and Dayoonira are twin sisters and went to the same school that Jacob and Marneao went. When Marneao and the friends plot to get Amy and Jacob together, Matt convinces Dayoonira to help then in exchange of a look change.

Production Notes
This is evidently a joke character, totally based on Osomatsu-san's Dayoon. Even her name is a reference to that.

The character started just like a 1-chapter-joke, but in the omake I said she was Amy's sister and in the end she does something in the story.