Mark didn't have a wide range of experience, but what experience he did have, he was good at. When he felt her mouth open a little, he caught her lower lip in a very light little nibble, and then sucked on it gently. Most guys failed hard at this, sucking like they would on a straw, but Mark had learned the gentler approach after many trials and errors. He kept one hand on her side to help hold her steady, but slid the other one up to her lower back and began making little circles along it, almost as if he was giving her a massage.