Kim Woo Bin surprised viewers into laughter with his blunt questions on the birds and the bees on the April 4 installment of 'Four Guys One Girl'!

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On the broadcast, the grandpa recalled his uneventful love story with his wife, "Back then, we didn't go on dates. There was nothing like that because we were busy making a living... During our newlywed stage, we were just busy working." Kim Woo Bin then asked out of innocent curiosity, "Then how did you get kids?", making the grandpa flustered.

When the grandpa also shared how he fell in love at first sight with his wife who wore pigtails at the time, Kim Woo Bin commented, "Father is the style to look at visuals... When did you have your first kiss?", to which he revealed that he couldn't kiss before getting married. The maknae son continued, "So you waited and then once you got married, you just did it", creating a hilarious awkward moment.