This girl is wearing what my girlfriend tells me is a tank top tee-shirt. It is the tee-shirt a girl might generally wear over a bikini. It has a very low neck and is generally designed to show off part of what you are wearing under the tank top—which, in that case of my girlfriend, might be a bikini top.
But this girl is showing us a much more effective way to wear a tank top. Firstly, don’t wear anything under it. Tis is a very important first step. Then, secondly, put it on sideways so that your cock-hardening primaries are exposed to maximum effect.