I'm never to sure where to draw the line since the nudity in quite a lot of art throughout the centuries can feel just as pointless sometimes --- BUT IT'S 'ART'!!!!!!
I've dabbled my fair share into arts and the problem is that it's tasteless and plain.
The designs are fairly simple (belts in a squeenix game, whodathunk) and the skin shown does not expand the concept or the representation of the character. The skin shown isn't even made to be erotic anyway; it just feels kinda pointless.
I like my eros even more when it has a meaning or represents something (well something other than half naked 15 y-o girls sell well in JP)
Don't read anything scorn in that last parenthesis though.