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Astin from Jessie's flashback
Astin was Jessie's childhood crush and one of the characters of the day in Crossing Paths. Astin also has a present day look-alike by the name of Austin. He is nameless in the Japanese version.
Astin used to go to the same school that Jessie was in. He left to become a Coordinator and, before leaving, asked Jessie to join him on his adventures. Jessie was torn between traveling with her crush and staying at school for her debut as a dancer/performer. Jessie ultimately decided to stay at school and has not seen him since his departure.