Birthday: August 21
Height: 154 cm
Weight: 48 kg
Blood Type: B
Favorite Music: Rock in general. Metal, punk, and other aggressive music is okay too. Beat is what counts.
Experience with Playing Musical Instruments: Started playing in Middle School. Three years of experience.
Family Structure: Family of four, both parents and a younger brother attending middle school. Average household of an office worker. She has no reservations about hanging out together with her brother.
Dwelling: Single-family detached home.
Commute to School: Walks (her house is in the same neighborhood as Mio's).
Preferences in Clothing: Pants over skirts. She likes to wear polo shirts.
Her Room: Messy to the point that there is no place to stand. Half-finished manga and snacks are scattered around. She tidies it up before it becomes a full-blown disaster, but it immediately becomes a mess again.
Favorite food: Rice. Rice comes before snacks. She values food that fills the belly.
Subjects She is Good at: Physical Education.
Subjects She is Bad at: Everything else.
Physical exercise: Her strong point.
Way to Pass the Time When Alone: Reading manga.
Weaknesses and Dislikes: Work that involves minute details, complex and fussy tasks.
Ritsu (or Ricchan, as nicknamed by Yui) is the self-proclaimed president of the light music club and plays a yellow Rick Marotta Signature Yamaha Hipgig drum kit with an add-on floor tom (in the opening credits only) combined with a cymbal set from Avedis Zildjian,though is shown playing a white Yamaha Absolute Series drum kit in the anime's closing credits.She has an ambiguous yet upbeat personality, much like Yui, but often has trouble remembering important club activities and announcements and gets constantly rebuked by Mio and Nodoka for forgetting to send in important forms concerning the club. Ritsu is cheerful, often likes making jokes and is sarcastic most of the time. She is skilled at brainstorming ideas that earn money for the club. Ritsu has shoulder-length, brown hair, with her bangs pulled back with a yellow hairband, and gold-colored eyes. She wears her school jacket open. She says she chose to play the drums because they are "cool," but she then admits that she has trouble playing instruments which involve intricate finger movements, such as the bass, guitar and keyboard.
She is a childhood friend of Mio and will often take the opportunity to tease her whenever Mio is cowering from something. She is also known to become easily jealous of Mio's other high school friends, even going as far as spying on Mio when on outings with them. Ritsu is always on the go and will stop at nothing for the success of the light music club. Despite her rough mannerisms and speech, she gets cast as Juliet by the majority of her classmates in their class play rendition of Romeo and Juliet and, in the end, manages to act like a proper girl. In the anime, she states her favorite drummer is Keith Moon of The Who. She is skilled at cooking. She has a younger brother named Satoshi.