Yes, you have the right idea for 1. The meaning would depend a lot on the context of what went before. But perhaps there was a child with a very sticky lollipop behind her, or perhaps someone with a lawnmower, or garden tiller? Something that might damage her skirts, or pull her in and hurt her. 'Skirts' is from the old days, when people wore several skirts over the top of each other, to fill out the shape. 2: Yes. Trapping him verbally, not literally. Trying to cleverly make him reveal some secret - a secret that would perhaps incriminate him, or get him into trouble. 3: A pet vanity is perhaps an indulgence - one small thing that she allows herself, or perhaps something that she believes she is better than than most people. 'A talent for dark' is less clear. It perhaps means that she is involved in witchcraft? Or just dark artwork: artwork that shows the darker, or less pleasant side of life. So - the one thing that she believed she was good at, was doing something 'dark'.