Tsumugi Kotobuki (琴吹(ことぶき) 紬(つむぎ) Kotobuki Tsumugi), otherwise known as Mugi, is a wealthy cheery cute girl with a gentle personality who plays the keyboard in the light music club. She was originally going to join the choir club, but after Ritsu Tainaka's false flashback she thought it would be fun to join the club.
Name: Tsumugi Kotobuki
Allies: Yui,Ritsu,Mio,Azusa,Rex, Sawako & more...
First Appearance: Dissolution! (K-On!)
Theme: BACK-ON - flyaway (Normal),The Word Alive - Heartless (Rage)
Ritsu, Azusa and Ui's surprise when they try to contact her at home). She often brings sweets and confectioneries to her friends.The tea set and the tea which they drink often are unusually high. Although she is a sweet and gentle girl, she is often weirdly entranced by the sight of two girls interacting closely together, sometimes imagining something more risque in her head (both Mio and Ritsu find this awkward at times). She originally intended to join the choir club, but joins the light music club instead after receiving an invitation and encouragement from both Mio and Ritsu. Mugi displays a rebellious streak occasionally, due to her wanting to deviate from her wealthy nature, and diverts from a well-behaved and mature demea
nor to the surprise of others. She also has a habit of getting a little too enthusiastic about experiencing new things that the others take for granted (such as ordering fast food, eating yakisoba at a festival, and purposely provoking Ritsu to hit her).
Despite her being wealthy, she also tries her hand at a part-time job at a fast-food restaurant. While a lot of things do not bother her, she is fairly conscious about her weight (just like Mio), and she gets a bit anxious when her family's staff start spoiling her friends during villa visits.
When she was child, She was been bulling by Bullies until she got rage. she beat them up and on and on. She cannot stop her Rage until the cure make her normal and never happen.