Canonically, she's more mischievous and sort of cocky, yeah. I mean, her whole lamprey stand operation is really a con - she makes humans night blind without their knowing, then makes them pay for the cure that she just so conveniently happens to have.
I like both versions, but it'd be sort of nice to see a more impish aspect reflected in the moemoe interpretations, sometimes. (This picture is pretty adorable, though.)
