Like I know most people don't wear bras underneath, I mean I certainly don't. But like, I noticed that when ever a girl is wearing pjs that their nipples doesn't show through their shirt and it looks like their wearing a bra. so I'm like are they wearing something under their shirt so it won't show? or is it type of pjs that you wear. I am so confused, I should know this since I'm a girl but I don't. I feel kind of embarrassed for asking this. *blushes* and for a bathing suit they have bathing suits that has built in bras right? What about those swim suits that sufer girls wear it doesn't have a built in bra. I know cause I bought one once. So what they do?