arm candy 
noun informal
A sexually attractive companion accompanying a person, especially a celebrity, at social events.We all have our places in this cosmic drama, and Burt's involves being the leathery arm candy and ‘drink getter’ of Southwestern widows....
- ‘I did the Hollywood thing for a while,’ says the girl from the prairies of Alberta, Canada, picking out highlights like the time she went to the Vanity Fair party with Madonna, Cher and Joni Mitchell as her arm candy.
- I go to a lot of meetings with men in the City, and they all talk about their arm candy, their secretary, their 30-year-old ‘babe’.