Gyaru-kami-sama's gotta punish that boy for complaining by making the skirt even shorter, I tell ya hwat. Also by turning all his boy undies into panties, too. No retreat from your destiny, Jun!
Seems like that little goddess spends her gyaru power in small portions now and then, so can never build up to the level needed to turn Junpei back into a boy. Clever planning, that.
P.S: that is an S-tier gyaru yukata! Don't let it go to waste!