Mila Kunis joined her boyfriend - or possibly fiancé - Ashton Kutcher on the set of Two And A Half Men. In a similar fashion to Brad Pitt's Friends appearance with then-wife Jennifer Aniston, the couple joked about their relationship whilst Kunis guest starred on Kutcher's sitcom.

Mila Kunis and Ashton Kutcher
Mila Kunis and Ashton Kutcher joke about their relationship in Two And A Half Men.

Read more: The TV Couple That Became Real: Mila Kunis & Ashton Kutcher

This was not the first time the couple have acted together as they both starred in the long running sitcom That 70s Show. The pair met whilst filming the show, which first aired in 1998 and ended in 2006. They may have known each other for more than fifteen years but the couple only got together in 2012 following Kutcher's split from his wife Demi Moore the previous year. Whilst rumours of the couple's engagement and Kunis' possibly pregnancy run amock, the pair filmed an episode for Kutcher's sitcom Two And A Half Men in which they joked about their relationship.

Mila Kunis Two and A Half Men
Mila Kunis guest stars as Vivien, a world traveller in Two And A Half Men.

Read more: Is Mila Kunis Pregnant?

Kunis, as THR reports, plays Vivien a world traveller who appears on Schmidt's doorstep and forges an instant connection with this fellow hippy-like character. According to reports, Kutcher's character Walden Schmidt shares a takeaway with Kunis as they discuss dating famous people. 

Mila Kunis and Ashton Kutcher The off screen couple share a takeaway and discuss dating famous people.

Kunis' character Vivien allegedly jokes with Kutcher's character that he "only dates hot actresses". Kutcher then tells his off screen partner "God no, I'd never date an actress. They're all crazy." Vivien attempts to refute his claims by reasonably stating "I'm sure they're not all crazy," but Schmidt is determined they are. Whilst Kunis, in the guise of Vivien ends their discussion with a snide remark aimed at their fans and the press, saying "Who cares who's dating whom; or who's engaged to who; or who has a sex tape that no one will ever, ever see!"

Mila Kunis and Ashton KutcherRumours regarding Kutcher and Kunis' engagement remain unconfirmed.