As the granddaughter of the school director, Haruka was born and raised in the pristine natural environment of Eiden island. With a warm-hearted and energetic disposition, her natural innocence has long since captivated the hearts of those around her.
Being not very well versed in the outside world, she often appears to be clumsy or obtuse, leading to her claims that ”my good point is my health!” despite consistently testing into the top of her class; especially on the subjects of math and science. Recently she has taken an interest in the newly transferred boys.

Mizuki loves to swim; in fact, the reason why she enrolled at Eiden is so that she could swim in the ocean whenever she wanted. With the soft currents and warm waters, she used to swim naked from time to time, but hasn’t ever since the boys saw her.
She is very athletic and a little boyish, making her so popular amongst the girls that she has a bodyguard squad, but she has no interest in them. Due to her lack of experience around boys, she sometimes comes off as a little hostile towards them, but she actually yearns to be in love. Also, she loves fancy accessories, just like any other girl.

Her hobby is to make money; she believes that ”even dirty money builds a houses” and swindles the boys out of their money by pawning off things like ”how to be popular among girls (false, of course)” and ”a picture of a naked woman (supposedly).” The only subject she’s good at is counting money.
Despite her less than timid activities, she’s actually quite shy and is uncomfortable being in a group.

She is a mysterious girl who doesn’t talk much and doesn’t like to mingle with other people, so she hardly has any friends—boys or girls.

Mei is the protagonist’s teacher. She is a graduate of Eiden Academy and in her mid-20’s. She attracts boys, including the protagonist, with her mature charm, which is sometimes used to control them.
Although unusual at an all girls school, she is very popular among the female students. The girls respect and look up to her, often coming to her for advice. When she drinks, her personality changes and she starts bawling.