Editing Kerista (section)

===Family life / polyfidelity / sleeping schedule===
The family structure of Kerista was composed of fidelitous groups called B-FICs (Best-Friend Identity Clusters). Keristans practiced non-preferential polyfidelity, which required consensus to accept a new person into the group.

Non-preferentiality was an important concept of Keristan polyfidelity, and had lofty goals but was more intended to keep people from coupling up. Keristans had a transitional celibacy period after joining a group of three months, sometimes waived.

A single B-FIC was composed of men and women who rotated sleeping with all of the opposite-sex members on a balanced rotational sleeping schedule. The sleeping schedule assigned each family member to sleep with a different opposite-sex partner each night. Since the BFICs were rarely balanced between men and women (typically more women than men), on any given night several family-members would have no partner to sleep with and were assigned a 'Zero-Night' when they slept alone. In addition to the programmed sleeping schedule, it was permitted to sleep with any opposite-sex family member at any time, which was termed a 'freebie'.