They were rumored to be potentially getting back together following her divorce announcement from Ryan Sweeting, and despite their denials, The Big Bang Theory co-stars Kaley Cuoco & Johnny Galecki may need to fend themselves off from rumors once again.

Did Kaley Cuoco Decide To Divorce Ryan Sweeting After He Skipped Out On Rehab?

The two attended a party for the Fallout 4 release with Cuoco's sister Brianna last week, and a photo posted to Galecki's Instagram has raised eyebrows about just how close the two co-stars-and former couple-are these days.

The post shows Galecki appearing to take a bite out of Cuoco's shoulder as she makes a funny face at the camera.

Kaley Cuoco Thanks Her Supporters On Instagram

 Hilarious night out in the LA Arts District w/ @normancook #BFFsbite @ludwig1965 @bricuoco

A photo posted by Johnny Galecki (@sanctionedjohnnygalecki) on Nov 6, 2015 at 11:45am PST

"Hilarious night out in the LA Arts District w/ @normancok #BFFsbite," he captioned the pic. Cuoco also shared an image from their night out on her own Instagram page, where she and Galecki flank her sister.

So fun tonight! #fallout4party @bricuoco @sanctionedjohnnygalecki A photo posted by @normancook on Nov 6, 2015 at 1:15am PST

"So fun tonight! #fallout4party @bricuoco @sanctionedjohnnygalecki," she wrote.

Cuoco and Galecki secretly dated for two years before ending their relationship in 2010, which prompted the rumors after she and Sweeting announced their divorce back in September after just 21 months of marriage.

Not long after the rumors started up, the two both took to social media to debunk them with pics that insisted they were just best friends and had no interest in being a couple again.

 No scandals / home wreckers / pregnancies here, y'all. Just profound friendship. @normancook

A photo posted by Johnny Galecki (@sanctionedjohnnygalecki) on Oct 14, 2015 at 11:03am PDT

Tags: Kaley Cuoco Johnny Galecki