promotional art for Dolphin Wave showing 4 anime style girls in black wetsuits, on the left side is a purple haired girl with tan skin jumping in the air in a centaur boobs and butt pose, next to her is a blonde girl bending her back in a 90 degree angle

Maybe their poses represent the waves

More from Dolphin Wave. Poor Hayate, that centaur boobs and butt pose she's doing looks so painful. D:  Ellen's pose is only slightly better, she looks like a Tetris block.  Maybe their poses are supposed to represent the dolphins... or the waves?

(Ad for Dolphin Wave, Honey Parade Games, submitted by anon)