mattress


mattress
   (in compounds and phrases) relating to copulation
   The common association of beds and copulating, in such phrases as mattress drill and beating the mattress. Mattress extortion is sexual blackmail or persuasion:
    So you con him into moving to sunny Florida. Maybe a little mattress extortion there. (Sanders, 1982)

How not to say what you mean: A dictionary of euphemisms. . 2014.