Akina Nanamura

A neighbor and childhood friend of Kazuto. She has considerable powers with the ability to attack with demon wards and to create barriers. Spoiler She sealed away Hydra's powers after Hydra crash landed on her family's shrine and started wreaking havoc. She seems to have feelings for Kazuto as she is always stopping at his bathhouse. However, she never acts on these emotions, which she greatly regrets at times, as he and the princess Valkyrie grow closer together. She later has to face the fact that they are in love and intend to marry. A couple of things to note is that Akina is a horrendous karaoke singer, and that she is quite self-conscious about the size of her chest. In the beginning of the 2nd season, Valkyrie uses her power to make Akina's breasts grow to an immense size (At Hydra's joke request), which turns out to be a satisfying moment for her. (Source: Wikipedia)