Most Helpful Guy
Like, if I was your boyfriend and one of my regular button up shirts? It's because
1) It's sexy because of no bottoms & extra skin show
2) It is the "freshly f***ed" or "had sex" appearance as mentioned by someone else earlier. Just means you have been naughty.
3) It's more a intimate thing and tells a guy you are his...cause you are wearing his clothes. It also, looks cute cause the size is too big.