Suzu is a young lady whose sister is assisted by Kantarou in the first case on the first episode. She has a mad crush on Haruka, and regularly visits to see Haruka and tease Kantarou. She's also friends with Youko and Rosary. Though at first Rosary don't show much interest in her Suzu continuously tries and became friends with her.
SpoilerUnfortunately, in the end, she dies from hypothermia. She shows up again however, after she has died, as a spirit. She believes with all her heart, that everyone she knows deserves to be happy. She helped somehow to get Haruka and Kantarou to being friends again. Her lingering attachment to the world that made her a spirit was also the thought that they should not be quarreling and instead become friends. She knew she was a spirit and had died. It's really sad if you truly see her from episode 1 to the end.
When she was small she knew her sister Miyako and her father was worried about her weak body so they do things gently with her around. Though because of that she wanted to die even more and couldn't make friends. Though when she met Kantarou's group that changed her and she was truly grateful for it.
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