From Sensation Scans:

Soda and Sukhee have known each other since they were little. Soda was the "hero" of the local kids, famous for her flying-chicken attack. While Sukhee was the new kid in town who tried to take over the playground and ended up getting a good beating from Soda. What really is the fate between these two as Sukhee challenge Soda to a fight each and everyday?