Lie beside each other in bed and masturbate yourself while he strokes his cock with a well lubed fleshlight. As you both get close to cumming he must slow down, but you can bring yourself to as many orgasms as you want. He can only admire your pleasure and wish it was his own. When you are done he must stop stroking, without cumming of course.
I thought this was sexy although that fleshlight is really freaky looking. There are much nice male toys than that!