Offer to wash his back

At thinking of possible ideas, your head could only come up with one, and probably the most cliché line.

"Hey, do you need me to wash your back?"

"What?" asks CJ, giving you a weird look.

"You know, cause you can't reach." you reason.

"Yeah, fine, go for your life." he says, passing you the soap.

You begin by massaging the soap into his shoulders. He may be 18, but his shoulders had broadened and made him look more man than boy. His killer shoulder blades poked out and you rubbed the soap up them, coming to his spine. You began cleaning down his back, letting your fingers lightly touch his skin. You enjoyed the slow descent towards the southern mountains. Before long, you had begun scrubbing the small of his back, sitting right above his ass. You rubbed the soap there for a long while, staring at the round beauty below. You were so ready for Round 2.