Ruriri, Mariru, Mariruri! Madamada gooru!

-Himatsu Nakahara

Himatsu, or Splash for those who get tongue-tied at her name, is the valiant leader of Uta Dan (Team Song). She's a transfer student from Japan, and while she has a good grasp on the English language, sometimes slips into using her native tongue for words she doesn't know, especially species names. She also unconsciously uses Japanese honorifics a lot of the time, since they've practically been pounded into her head.
Himatsu suffers from a gender swapping ailment not very uncommon in her species. When an Azurill evolves, it has a chance of changing gender for whatever reason. Himatsu was one of the affected. Upon her first evolution, she switched gender to male...then switched back a week later. Ever since, her gender has been in flux. While her main gender is still female, she will become male once in a while for a random amount of time. She strives to keep this a secret, and she changes her wardrobe when she's male, leading the student body to think there are two very similar-looking Azumarill running about.
Himatsu's dream is to become a famous idol, so she has assembled a team based on song and dance. She's become close with her friends and wants to take them to the top with her.