@Gargron If you cat's nails bleed, you have cut too deep and probably hurt them badly. Always be very careful and just cut the sharp tip, do mot go anywhere near the pink area of the nail. It's the equivalent of your nail bed. Every time you nick it, you make it harder to trim the next time, and you risk allowing infection into the nail. As you gently and carefully trim your cat's nails, over time they will learn that you aren't going to hurt them, although they may still remember a trauma.