I love this addition to my bag of tricks! After getting familiar with a pinwheel and having already been a fan of fingernails on my skin, this seemed like the next step and, freaking wow. You can be gentle or you can draw a couple drops of blood with these, and I'm in love. The scratches that get left behind heal pretty quickly but stay visible for a couple weeks (and while they're still tender, brushing them against something simply reminds me of the last wondrous session I had). If you're into scratching and marks like I am, I highly recommend this gets added to your bag as well!