Julia
Julia is Mizuki's best friend from America who visits Japan for a month of study. Pretty quickly into her stay, she realizes that Sano's already figured out Mizuki's secret—that Mizuki's actually a girl.
To mess with the situation (and probably have some fun), Julia decides to spread the rumor that she and Mizuki are lovers, basically to see how Sano would react. It's a decent strategy for reading the room.
Nakatsu doesn't take it well. He's already jealous of how close Julia and Mizuki are—closer than he's able to be—so he ends up really disliking her. The feeling's mutual. Julia calls him "Monkey Boy," and they generally get on each other's nerves.
Content compiled by AnimeList.moe from publicly available sources.
