A horrific "game," where participants (typically
adolescents with permanent erections and nothing better to do) sit together (often in formation around a focus, say a tv or
computer screen) watching porn, and masturbating furiously. The
criteria for "winning"/losing vary from game to game, but there can be unpleasant consequences for he who shoots before/after everyone else. Most often, however, whoever fails to shoot before the allotted time has elapsed is said to have lost.
See: bukkake
M: Heard things got
pretty wild the other night, what happened?
H: They were playing beat the clock..
M: Seriously? That's really nasty.
H:
Haha yeah, isn't it?
M: *sigh* .. The
inhumanity..