Jim pulled his hand free, flexing fingers and wrist to work out a kink. He gave a tiny smack again, "Ass up, keep it there." It would put tension, strain on Spock's legs to keep it up and steady.

He laid the length of beads across Spock's back, speaking in that low tone, "Do you even know what these are for?" Not letting his thoughts transmit the best he could by keeping his hands from touching skin.

He poured lube over the beads, letting it drip down to the pale green skin.