Fencedude said: The "aria" tag has all of two images in them, of two different characters.
That's because the character Aria is now aria_(sister_princess). The aria tag used to be a mishmash of the two (plus some other things), though, since most people weren't separating them. It makes it a bit harder for new people to locate them, yeah, but I think it's easier for them to get a disambiguation page and pick out the right tag than to wonder why they got all these images of something they didn't want (which they would if only one of them was made more specific).
Also, one of the two images under "aria" is mistagged. Let me fix that.