massage à trois
n.— «Sometimes, though, they let unwitting customers become participants in what one might call a massage a trois: While Mathilde washes one man’s hair, her husband kneels and begins biting her buttocks through her thin cotton frock.» —“To have, to hold and to cut hair Kinky ‘Husband’ needs a good trim” by Bill Morrison News & Observer (Raleigh, N.C.) Oct. 16, 1991. (source: Double-Tongued Dictionary)
Further reading
Amanda in Reno, Nevada, has a dispute with her husband. Is it okay to ask if something is any comfortable? This is part of a complete episode.
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