Actress Lee Sun Bin surprised everyone on a recent episode of SBS's Whenever Possible by mentioning her longtime boyfriend, Lee Kwang Soo, on air. The cast and viewers loved it—lots of laughs and smiles all around.

On the January 27 episode, Lee Sun Bin and Kim Young Dae showed up as "gap friends," which basically means they hung out and shared little moments together—just walking around Bongcheon-dong in Seoul, talking about their lives and work.

At one point, Kim Young Dae talked about how he started out as a model before getting into acting. Then host Yoo Jae Suk jumped in, bringing up Lee Sun Bin's boyfriend. Yoo pointed out, "Kwang Soo was originally a model too."

Kim Young Dae laughed and shared a funny story about meeting Lee Kwang Soo not long ago. He said, "He's so funny. He sat me down to give me good advice and talk seriously, but I like him so much that I started laughing just by looking at his eyes."

Apparently, Kim kept fighting off a smile the whole time, and when Lee Kwang Soo finally noticed, he asked, "Did you just laugh?" That only made Kim laugh harder.

Lee Sun Bin couldn't resist jumping in. Smiling, she joked, "Didn't he learn all that from Yoo Jae Suk?" which got Yoo's attention right away. He played along, grinning, and said, "He learned everything from me." The whole group cracked up, and the mood just got lighter from there.

AllKpop called this exchange one of the best moments of the episode. Fans especially loved how Lee Sun Bin's quick wit and easy banter gave everyone a rare peek at her relationship with Lee Kwang Soo—usually, they keep things pretty private.

Whenever Possible is all about finding small joys in the middle of everyday life. You can catch it every Tuesday at 9 p.m. on SBS.

In other news, according to Koreaboo Lee Kwang Soo and Lee Sun Bin sparked marriage rumors after photos from a Solo Prince stage greeting showed the longtime couple looking especially affectionate, drawing excited reactions from K-netizens who said they "look so in love."