Kelsa is a member of the Shi family, and part of the Wei clan. She is the sister of Wei Shi Lindon, who is the protagonist of the story. Currently, she is an Jade on the Path of the White Fox.
Kelsa lives in the Wei clan along with the rest of the Shi family as a Copper on the path of the White Fox. She is considered the pride of the family. After Lindon returns with a spirit-fruit from an ancestral tree, the family argues for Kelsa to receive the whole fruit in order to advance her quickly to Iron in time for an upcoming tournament with the other clans of Sacred Valley. Kelsa instead divides the fruit in half, giving the other half to Lindon.
Days later, before the tournament, Kelsa advances to Iron while sparring with Lindon.
It is revealed that Kelsa survived the destruction of the Wei clan. She is on the run, either by herself, or with a number of Wei clan survivors. She has been stealing food from the Heaven's Glory and Fallen Leaf Schools in order to survive.
While on the run from several hostile Irons, Kelsa encounters Orthos, who reveals that her brother is alive. Orthos then protects Kelsa from the pursuing Irons.