Having played the game (I'm doing it to collect rare pokemon for my 8-year-old nephew, don't judge me, SHUT UP!!) then when you beat her challenge, she teaches you the special dance to learn water-based Z-moves. Most of these dances are ridiculous-looking. Suiren/Lana here teaches a dance that involves waving your arms around to represent waves, and that's the pose it ends up in.
