"It takes two, to Tango..." 

A woman meets with her lover, who is also her husband's best friend. 

They make love for hours. Afterwards, as they lie in bed, the phone rings. Since it's the woman's house, she picks up the receiver. The best friend listens, only hearing her side of the conversation: 

"Hello? Oh, hi... I'm so glad that you called... Really? That's wonderful... Well, I'm happy to hear you're having such a great time... Oh, that sounds terrific... Love you, too. OK. Bye-bye." 

She hangs up the telephone and her lover asks, "Who was that?" 

"Oh," she replies, "That was my husband telling me about the wonderful time he's having on his fishing trip with you."