日渡, Shimauu
A friend of Fuuka039s given name unknown who is in the same homeroom. Her first official appearance is in chapter 45 when she visits Fuuka039s home and recognizes Yotsuba from her trip to their high school in chapter 40. Hiwatari has a somewhat eccentric personality. She is normally called by her nickname Miss Stake Shima? due to a quotmistakequot she made when she first introduced herself to her class in Japanese shimau used as an auxiliary verb can mean to do something by accident hence the pun. Source: Wikipedia