This is a two-part game.

In first part, the girl has to maintain the guy's hard-on for as long as she
can without letting him cum. She should bring him as close as possible to an
orgasm without actually getting there. The challenge is to keep the guy hard
for the longest time.

Start a timer when the guy gets his first hard-on and measure how long the girl
can keep him hard.  If his dick softens - stop the clock. If he cums - stop the
clock.

In the second part, the total hard-on time becomes the girl's attention-time.
The guy has to give the girl his full attention trying to please her during
that time period. He isn't supposed to enjoy it. His job is to bring her to as
many orgasms as he can during that time. The girl should be a passive
participant - not making any efforts to please the guy. Unless the girl asks
for it, the guy should not use his dick (this is her time, not his).  Hands,
tongues, fingers, feet, lotions, rubbing oils, vibrators and dildos and all
ok.