Yuuri is the president of the School Life Club. She keeps a detailed record of food, electricity, lessons, and other resources and activities. Yuuri is usually very calm and mature, and acts in a collected and proper manner. She also is quite serious, always looks after her comrades, and is not afraid to scold someone when they put themselves in danger pointlessly.

In the manga:
When the girls leave the school, Yuuri demands they stop by a local elementary school, wanting to look for her younger sister, Ruu. She eventually finds her and brings her back to the group.

It is revealed later that Yuuri suffered a mental breakdown over the course of their journey to the university. Ruu is a hallucination that Yuuri built up around a bear plushie that Yuki tried to leave at the elementary school.

Towards the end of the manga it is shown that Ruu actually existed, but that she died long before the events of the story in a traffic accident, under Yuuri's eyes. Yuuri still blames herself for not being able to stop Ruu from running out into the street to recover her hat.

In Otayori:
Yuuri is tasked with planning for various long-term matters, and lives in the Restoration District. She occasionally does field work, which involves taking out any infected the team encounters, and rescuing survivors.