Jim smirked more, forcing Spock's ass up just a little bit higher, and grabbed just behind the first bead. "Just relax, Spock..."

He rubbed it in slow circles against the sensitive flesh, waiting until he could feel the smallest relaxation before pressing it in. It would take a few beads for the sensations to really hit, as the body sucked in each bead and relaxed around it, holding it in tight.