Mitsuru Kotokura is a young woman who works and lives at the shrine serving Shizuki Ugaya, the grandmother of the protagonist Tamaki Kasuga. She is the daughter of the Kotokura family, a branch of the Ugaya household, and serves as an attendant, managing the household duties for the family. Mitsuru is characterized by her extremely polite demeanor, which can sometimes make her appear emotionless or doll-like to others. Despite this reserved exterior, she is a capable and reliable individual. She is an excellent cook and skilled at all forms of housework, often taking care of the daily needs of those living at the shrine. Mitsuru possesses a supernatural ability to create invisible barriers. When someone is caught within one of these barriers, it is described as feeling like mizu-ame, a kind of thick syrup. Her role in the story is primarily supportive; she assists Shizuki and the five Guardians tasked with protecting Tamaki, the Tamayori Princess, by maintaining the household and offering quiet aid. Her key relationship is with Shinji Inukai, one of the five Guardians. She initially appears to have romantic feelings for him, but it is later revealed that she is actually his twin sister. This discovery reshapes their dynamic, deepening the personal connection between them. Throughout the series, Mitsuru remains a calm, efficient, and loyal presence, providing a stable foundation for the other characters as they face supernatural threats. Her development is subtle, revolving around her growing bond with those at the shrine and the revelation of her true relationship with Shinji.