You say that, because you are focused a little too much on just Helena. Actually, there are several characters, where Team Ninja graphically screwed up in the one or other regard.
Brad Wong's hair for example is very low polygon, Eliot's default hair has really low resolution textures, they forgot to give Ein's hair some sort of shine (even though Hayate's hair does shine), Rachel's ponytail is weirdly twitching, when she stands still in her victory pose, Hitomi's hair has serious clipping problems and Hayabusa's hair has low resolution textures, his ponytail is not really better than Helena's and in his loser pose, there's some graphical error going on.