Ashton Kutcher and Mila Kunis "hardly left each other's side" at a Hollywood function this week.
The pair attended the wrap party for Ashton's upcoming film Jobs Thursday night at Los Angeles eatery Duplex.
Ashton and Mila are rumoured to be dating and were recently spotted enjoying a kiss, although neither has confirmed the romance.
The nature of their relationship was clear to partygoers.
"[They] showed up as a couple and left as a couple," an onlooker told People magazine.
"[Ashton and Mila] appeared to be lighthearted and in good spirits, and hardly left each other's side. "They stayed within five feet of each other practically the entire evening. It looked like young love."
The gregarious couple were expert conversationalists.
"[They] were totally comfortable," the source recalled. "They were very friendly and spent a lot of the night engaging others in conversation while maintaining close and casual affection."
The lavish affair hosted 300 people and boasted guests like Diddy and Dermot Mulroney.
Mila and Ashton have been friends ever since they appeared on TV programme That '70s Show together. Things are said to be going well between them, with claims they are already sharing a home.
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