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Austin (Japanese: タイキ Taiki) is the character of the day in Crossing Paths. He is the mirror image of Jessie's childhood crush, Astin. Jessie even mentioned that they could be twins.
Austin first encountered Jessie at the lake after her Dustox followed his, a Shiny Dustox, there. He mentioned that Dustox come to the lake in order to perform the crossing in which they gather by the lake and fly over Dustox Flower Field located near Mt. Coronet in order to mate. Jessie's Dustox seemed to have chosen his Dustox for its mate.
After a lightning bolt hit the rocks that dammed the lake, it began to drain. Both Jessie and Austin used their Dustox to help put water back in the lake by using a combination of Confusion, by Austin's Dustox, and Whirlwind, by Jessie's Dustox.
In the end, Austin releases his Dustox so it can be together with Jessie's.