I am a weilder of a set of tittays and I approve this message.shootthebandit said:
There's an art to appreciating a thing, boobs are no exception. Staring? No no no.
There's a polite way to glimpse and even appreciate said objects, you may even come for a closer look as long as you tell the wielder of the boobs that her costume is great and she obviously worked hard on it, and looks appropriately like the character she wants to portray.
That maximizes your time to appreciate said boobies if you wish, without coming off as maximum creepy, and you've also given the lady a self esteem boost in a way that matters to her, and is less about her jubblies. For extreme cover up, make sure you watch her eyes for at least 5 seconds and possibly get a friend to talk and cover each other while you talk.
Mentally vacant staring and glances is the pinnacle of rude. So plan, think, THEN approach. As you should with anything.
Staring is rude, even fully dressed, so don't do it to women or men who prefer to masquerade as more scantily clad fictional characters. They're there to have fun and to show off their work, not necessarily their bodies.
(Yes I'm looking at you fan girls, staring at the guy with his chest exposed, I see you doing it too, stop that, either plan your approach, or you have not earned the right to be staring at the goods in such an ill tasting fashion! Keep it classy)