It's Arika's first day of class and she's determined to start off on the right foot. However, other people within the school have different plans for her… as one of her uniforms ends up for sale in an Otome idol shop. And if Arika and the rest of her friends don't solve the mystery behind her disappearing uniform, she may be forced to leave school before she learns anything! However as one culprit is discovered, another mysterious figure will come into Arika's life in the form of an unknown sponsor, someone who will pay for all her school expenses, on the condition that she writes to him once a week. And she'll have a lot to write about, as Arika and her classmates face off against a phantom presence in the school pool, and discover an ancient power known as the Harmonium. Genre: Action/ Fantasy/ Sci-Fi.