I really like these while on my period. I like the lace sides as it gives more stretch and room and makes them more comfortable. I’m XS in all their undies except the thong. Other brands I’m typically a small but Proof runs a bit bigger in sizing so XS fits nicely. These work nicely under jeans too. Even though they are called cheeky, they cover the rear in a nice way and don’t ride up. The everyday, the two lace side undies and the thongs are my favorite. I wear the thongs everyday and no longer need panty liners.