I've known folks who have holes or drop-down flaps to allow for bathroom needs, so they don't have to completely de-suit to go potty. Some of those same furs have holes that close up seamlessly so you can't see that they have one, even if clothes are not worn over the suit. I'd say this one is a bust, even though I'd heard the same rumor once, long ago. It's a popular rumor, even though it is most likely false.

ill fitting pants that look like someone took some scissors to an old pair of jeans? probably a fuck suit. Pants that fit the general theme? just costume.

i actually stopped wearing shorts on one o my fursuits for this reason