Have the same in white and it's perfect. Same size in black turned out bad, to wide and long

The material of these pants is extremely thin and see-through. They are quite stretchy and comfortable but I don't think I would wear them without something underneath. That being said, I cannot wear them at all because the zipper does not work. It was stiff the first time I tried them on, and now does not budge at all. There is nothing stuck in the zipper, so I don't know what happened. The zipper is also located at the back, which makes it way more difficult to fix if it gets stuck. There are also loose threads at the front button.