there are many types of FLR relations and some of them doesnt use cuckolding method. but according to me for a deep FLR relation cuckolding and husband constant chastity are required. so that the husband pushed a servant, slave role in the marriage and wifey gets full power, freedom and domination of the marriage. even if wifey doesnt have a regular bull, she should be open to date with other guys, make sex with them, having other lovers etc. if she wants one day.