It sounds like you're asking for a (likely for a game, interactive fiction, or simulation) involving a CFNM (Clothed Female, Naked Male) scenario set in a mixed swim environment (e.g., a pool, beach, or changing area where genders swim together, but with specific clothing rules).

Private boat rentals allow groups to create their own rules away from public scrutiny. Etiquette and Consent

For nude swimming events, safety and hygiene are critical. This includes clean facilities and sometimes the presence of lifeguards.