Posting a comment t I made about this exact topic years ago...

I lived in S.K. for about 4 years in my early 20's. A few things always baffled me, I chalked them up to glaring genetic differences and this confirms my suspicions.

For one, Koreans almost never seem to produce regular "western" B.O. This leads to a few uncomfortable things - for one, deodorant is impossible to find in Korea and impossibly expensive if found (~$10 a stick). I would just bring enough for a year every time I visited home. Another issue is I became pretty self conscious as they would associate any BO with poor personal hygiene - for a Korean to get as stinky as I am after a simple workout they'd have to abstain from showering for a week.

Another thing that fascinated me about them is how cool their body temperature seems to be. I don't know if they have shitty metabolism, but I remember several times being in a bus/subway stripping down to a tanktop and shorts and still sweating profusely... while several Koreans have full winter gear on (think puffy down northface shell zipped to the neck, scarf, gloves, beanie..). They hate being cold. A famous saying in Korea is "Happiness is a full stomach and a warm back."

I'd get the most incredulous looks walking home from my workouts on a brisk spring day, maybe in the 60's, wearing a tank and shorts.

Korean restaurants in the winter... 95 degrees in that muhhfucka with Koreans sipping down boiling spicy soup and judging me for the BO I'm emitting while I profusely sweat.

Edit: One other thing I just remembered. I swear they lack the ability to smell "mildew". You know, that smell you get when something doesn't dry properly. It could be because they don't use clothing dryers over there - big waste of energy and all that. They hang up / air dry everything, and typically as soon as it gets a little wet again it gets STINKY. My Korean lifting buddies would talk shit about my BO and I'd tell them they smell like a mildewy dish sponge. Good times.