Mashiro Tsukinomori

Akiteru's cousin, she's also in his class at school. Usually reserved, she is particularly cruel when it comes to Akiteru. She is a fan of everything under the sea. Her LIME profile picture is a seashell.

Spoiler, click to view

She secretly writes under the pen name of Makigai Namako. As Namako, her LIME profile picture is a sea cucumber.