Lets start with 1/4 (used to be 1/2) of the company partners, silver fox Roger Sterling and go from there. Roger slept with and eventually married Jane, Don's secretary who lived on Jane Street and it was a cute joke. Everyone hit on her when she first got to Sterling Cooper but she gave it up to Roger and got rich. Before that he had an affair with Joan Holloway before she found a cute doctor and changed her last name to Harris. They reconnect in season 4 up against a fence. It's hot. She used to have a relationship with Paul Kinsey but it was implied that she broke it off because he talked too much about it. He's made moves on Peggy, who rejected him and things got awkward. Peggy did get it on with Pete the night of his bachelor party and then once again in the office, which knocked her up. She gave the baby up for adoption and then started an affair with Duck, yes 'Duck' last name Philips that Don hires to get more accounts into the company. Ken hits on everything that moves, except for Sal who expresses a serious crush on him even though he's married. Harry gets drunk on the night of the Nixon/Kennedy election and has sex with his secretary Hildy in his office, and later regrets it. Things get awkward. After Don divorces his wife, he gets engaged to his new secretary Megan but continues to sleep with every girl he comes across, strangely avoiding the office and therefore being somewhat on the outskirts of the Sterling/Cooper/Draper/Pryce sex-a-thon. Lane Pryce hasn't hooked up with anyone yet because everyone thinks he's uptight and awkward. Bert Cooper had a long standing affair with his secretary Mrs. Blankenship and seemed very distraught when she dropped dead at her desk. Shit happens. Lois is annoying and no one wants to have sex with her. The end. For now.