NWOT Fleece-lined Black Pants (large fits like a size small)

These pants run small. The large size is more like a small. I bought them to keep myself warm, but they are tight on me, and I wear a size 6. They are lined in fleece. They have never been worn. I wish I could tell you what the pants material is, but, unfortunately, the label is in Chinese. It is not leather, but it is very soft.