I'm not sure if this is a bug, but anytime I decide to wear the Wolf School Jacket, my shirt does not appear. It looks like I'm wearing only the jacket and nothing underneath.
It is a bug try constantly changing clothes until it is fixed at least that is what I did to fix it
Not necessarily a bug. Some outer torso clothes visually 'override' the clothing in other slots. Certain jackets do it, all the dresses do it (dresses tend to override both the shirt and pants visually). It's probably to stop clothes from clipping through each other and looking stupid.