She has long brown hair usually kept in a ponytail and dark gray/silver eyes.She wears the standard SSS uniform with her sleeves rolled up to her elbow. She also wears the GirlsDeMo accessory in her left thigh. She is seen carrying a guitar, mostly she used it in the performances during the diversion and Girls Dead Monster practices.
She has a candid personality and likes to play mahjong, which she has incredible luck with. In actual case, she cheats to win. She is strict when it comes to practice their new songs and she was always angry with Yui (probably because of messing the rhythms or if Yui had said something that she didn't like).
According to Hinata, she is "really athletic" (main reason for wanting her in his baseball team), though she wasn't shown playing baseball in the ball game tournament. She also says negative remarks, such as she rejected Hinata's request. She is good friends with Iwasawa, the leader of their band.
According to Hisako, she lived her previous life as a member of a band. However, a sudden incident — the main vocalist of the band committing suicide — has shook her, and she has never held a guitar since.
Things changed, however, when Hisako heard Iwasawa play the guitar one day in the Afterlife.
Hisako finds Iwasawa running from teachers who want to stop the latter's guitar playing in the middle of class period. She offers refuge to Iwasawa because she is personally moved by Iwasawa's performance and she invites her to play with her on the music room; at this time, Iwasawa discovers that Hisako has a playing style very similar to a band named Sad Machine. Hisako then offers her a chance to form a band with her.
Although Iwasawa is not yet ready to form a band with her, Hisako continues to play alongside Iwasawa; at this period, Iwasawa has finished composing "Crow Song". Hisako still wasn't able to recruit Iwasawa into the band she is planning to form, and she instead decides to ask her perform with her in an unexpected concert at noon.
In episode 3, when Yuri and the rest of SSS invaded Angel's room, GirlDeMo was tasked to distract the students off their doms so Angel will leave her room and come down to the sports hall. However this concert was later interrupted by the teachers.
When an NPC teacher threatened to throw Iwasawa's guitar away, she snatched her guitar and started playing My Song. Hisako knocked the NPC teacher, who was locking both her hands at her back, and rushed into the sound room to set the mic on Iwasawa to its maximum. Hisako was also the one who broadcasted her singing through the whole school which caught Angel's attention and directed her back into the sport hall. The one who mentioned Iwasawa's name after she disappear was probably Hisako.
Hisako had showed to be quite knowledgeable over the PA system (Public Address System) in Afterlife School when she broadcasted Iwasawa's singing. It was not mentioned how she gained this knowledge.