Goo Jun Yup revealed Kang Ho Dong likes to get naked when he's drunk.

SEE ALSO: Kang Ho Dong reveals why his son is afraid of him

On the July 14th installment of 'Knowing Brothers', Goo Jun Yup revealed, "I'm happy to see Kang Ho Dong. We haven't seen each other in a while. Do you remember me?" Kang Ho Dong responded, "Did I drink alcohol? Tell me."

DJ KOO then said, "You don't remember the birthday party? For the second part of the night, all the men went home. Since it was all guys, Ho Dong wanted everyone to take their clothes off. I'm older than him, so I didn't. That's scary. Do you know how scary it is when he takes his clothes off?"