From the Game's Introduction:
About SLURPS
SLURPS is an acronym for Simplest Little Unitarian Role Playing System. Each Player takes on two different roles, that of Divinity and that Divinity's Supplicant. In the unitariverse of SLURPS, every Supplicant carries his own interpretation of the Divine Being. And according to the rules, each of these interpretations is true.
The material required for a game of Slurps is a pair of ten-sided dice, of different colors, and writing supplies. This is always rolled as a percentile, meaning one die is always the tens digit, and the other is always the ones digit. A roll of 00 is read as one-hundred.
Supreme Being
Where most other games have one gamemaster, SLURPS gives each Player a chance to be Supreme Being. Every Player takes a turn at being Supreme Being at least once. When you are Supreme Being you create the locations, situations and any non-Supplicant characters, as well as control your Supplicant. You basically take the role of a gamemaster who also plays a character. Try to stay consistent with what the other Players have created before you as Supreme Being.