Kaley Cuoco
Kaley Cuoco and Karl Cook attend The 22nd Annual Critics' Choice Awards in 2016 Getty

Lovebirds Kaley Cuoco and her boyfriend Karl Cook frequently post adorable and romantic photos on Instagram. Recently, the couple posted a snap of them locking lips, with two clearly visible rainbows in the background.

The Big Bang Theory actress, who recently attended the Comic-Con in San Diego, spoke about her adorable "double rainbow kissing photo" with Extra TV. She said, "I mean..wasn't that great? I couldn't have written that in."

Her co-star Kunal Nayyar chimed in and asked "Are you sure you didn't just put that double rainbow in, in a filter?" Johnny Galecki too chipped in and joked, "Whats your name your Instagram, I am going to follow you?"

Then the entire gang surfed through their phone to find the snap, as Galecki said, "Oh My God" Cuoco said, "It's pretty good. I mean it was pretty romantic." However, the gang agreed that her best pic was the one from their rafting trip, where the 31-year-old star is seen giving horrified, expression as Cook gives a thumbs up to the camera.

Nayyar said, "That's the best picture I've ever seen." Gushing about her recent rafting trip the Royal Gorge region on the Arkansas River, Cuoco said, "My boyfriend is a thrill seeker and I'm doing all this crazy stuff and I look horrified."

"I did it and I actually had a great time. Rafting was super fun — I would actually do it again," she added of her adventurous trip.

The Big Bang Theory actress gushed about her romance with Cook in CBS chat show The Talk, back in 2016. She said, "I'm so happy... I can't stop smiling, life is so, so good. We met at a horse show, I finally found my horse guy. It was very meant to be."

The star of the hit CBS show admitted that Cook is a great person. "He's an amazing rider, amazing equestrian, and a great human. We shared a passion for horses and dogs ... It's been lovely."