Jennifer Aniston's 'Horrible Bosses' co-star wouldn't sleep with her if she asked as he is married.

The former friends star plays a sexual predator who tries to blackmail her happily engaged employee (Charlie Day) into sleeping with her in the new movie and although Charlie's friends don't understand the dilemma he would have no trouble refusing her or her character in real life.

He explained: "She gets to the point of blackmail. For my character, and a lot of people have said to me 'I can't understand why you wouldn't just sleep with her.'

"I am a happily married man in real life and if she was asking me to sleep with her I wouldn't sleep with her. It doesn't seem like such an outrageous thing.

"For my character, yeah, it might be a little extreme having her killed. But her character really is giving me no option. It's either sleep with her, or lose my job, or at the expense of my marriage. At a certain point, it starts to make sense for my character, who is not the brightest bulb, that maybe I just should rid the earth of this woman."

Charlie was the first to sign up for the movie which co-stars Jason Bateman, Jason Sudeikis, Kevin Spacey and Colin Farrell and revealed he felt like the "luckiest guy in the world" with the cast that signed up.

He explained to Collider: "I think I was the first one to sign on to star in the movie. I really enjoyed working with New Line last summer and I wanted to certainly wanted to stay in their comedy family I guess. I felt like a pig in shit or the luckiest guy in the world with the cast that followed. I had no idea who I was going to be teamed up with and I was a little worried about it. I was very excited when they came on and basically called Sudeikis and begged him to come on too. So that was my process."