But if i wanna change it, then the guy has 2 clothing (Default and Mod)
I assume that you mean
"the guy is wearing his normal clothes in addition to the modded clothes, and the two items are clipping or overlapping each other in an ugly way."
But assumptions are notoriously unreliable. It's helpful to
include a screenshot when reporting a problem, because it makes assumptions unnecessary.
Open up the in-game menu. On the first tab (which is named "Scene") the rightmost section controls the appearance of the male character. The topmost items refer to the guy's arms and his sexual attributes. There's a small darkly-colored line along the right edge, which you might not immediately recognize. It's an elevator bar. Use this bar (or the scrollwheel on your mouse) to scroll down.
At the bottom, you'll find selectors for the guy's clothing. Use the left selector button (◄) to switch these controls to "None". You might decide to leave his shoes in-place (if the modded costume
lacks shoes) or you could remove them as well.
As a general rule, male clothing mods will
not respond to the RGB sliders. You're free to tinker with them
(regardless of whether or not you've already removed the standard clothing items), but please be aware that the sliders probably
won't change the appearance of the guy's costume.
