Amana Osaki's older twin sister. Tenka is a shy girl with a rather low self-esteem that thinks that she isn't cute and even good-for-nothing, but seems to have a desire to change herself. She has low self esteem due to always being so tired, shy, and feeling incompetent at everything except video games and napping, but her desire to be a shining idol alongside her beloved sister gives her the drive to still do her best. She is in her 2nd year of high school.