Jennifer Lopez has one thing on her mind: sex!

Lopez, 40, guest stars on CBS' How I Met Your Mother in an episode airing Monday, March 8 at 8 p.m.

As a femme fatale sipping a drink at the local bar, she trades barbs -- and dirty talk -- with Barney, the lovable womanizer played by Neil Patrick Harris.

While they discuss a certain self-help book called Of Course You're Still Single Take a Look at Yourself You Dumb Slut, (!) Lopez's character reveals to Barney how many dates it'll take to get her into bed.

How many? Watch the hilarious clip and find out!