I'm 5'5 115lbs and find these to be a tad loose on me. They're surprisingly comfortable and flattering though. They look just like the picture.

You can see in the picture that they're a little loose on the model and the "bandages" are not perfect. They criss-cross crookedly in some places and not at all on the top. Obviously, the bigger you are the more likely they'll be see-thru on you (they aren't see-thru on me but they are really pushing it, so I can see that they might be on others since they're "one size"). I don't know what kind of material they're made out of--i was expecting costume material TBH, but I really like the way these feel! They are super soft and smooth (not as thin as I thought they'd be).

 Either way, do not expect these leggings to have much longevity. I would expect them to fall apart if I put them in the wash and I haven't tried hand washing them (probably won't bother).