Yumi Ogura

Yumi seemed to be shy, as she didn't talk much and was very quiet. She was concerned about Class 3-3's countermeasures, working with Izumi and Takako. Yumi was a calm, gentle, quiet, and innocent girl, contrasting with Izumi's harsh personality and Takako's cold demeanor. She often blushed. thumb|left|Yumi in her room. Yumi was good friends with Aya Ayano, as well as Junta Nakao and Takako, with whom she often spent breaks. She was also very close to her reclusive brother, Atsushi. Her brother's and Aya's deaths devastated Yumi and caused her to lose her sanity. She developed a strong hate towards Mei Misaki, blaming her for their deaths and wanting to avenge them. She followed Takako over the edge and attempted to kill Mei in Episode 11, which only led to her own death. In the manga, Yumi isn't hostile towards Mei after the class stops ignoring her and Kōichi. She and another girl later talk with Mei, much to Kōichi's shock. It could be that they were on more friendly terms. In the novel, Yumi is a quiet, calm girl with an open mind. She is on good terms with Mei and Takako and has a somewhat neutral relationship with Izumi. In the film, Yumi is shy and very quiet. She rarely speaks and isn't seen much. It is unknown if she is on friendly terms with Takako and Izumi. She also panicked when the inn was set on fire, attempting to run but falling onto the floor. This causes another student to fall from the second floor to his death. She still ignores Kōichi and Mei, even when the rest of the class stops ignoring them.

Yumi was a slightly tanned girl of below average height. She had shoulder-length brown hair with a pink hair clip and light golden-brown eyes. She was usually seen wearing the Yomiyama North girls' school uniform. She was one of the few main characters not seen outside of school, so her casual clothing is never shown.