Cher's boyfriend upset as Kevin Costner makes move on star: Source

Kevin Costner and Cher reportedly have been flirting with each other.

As per the latest findings of RadarOnline.com, the songbird caught the attention of the American filmmaker during the 14th February performance on SNL: The Homecoming Concert.

While the legendary singer enjoyed Kevin’s attention, her boy-toy was reportedly bothered by his presence.

"A.E. was very upset – he felt emasculated in the presence of a stud like Costner," the insider also explained.

The source also addressed, "It's not like he can compete with Kevin, who's the biggest star of his generation.”

In conclusion, the source noted, “Now that he's seen how flirty Cher was with Kevin, A.E. worries she's just keeping him around for arm candy while looking for more action."

For those unversed, Cher has been collaborating with her 38-year-old music executive boyfriend on her new and last album.