This was the top comment in the YT comment section:
For those that don't get the meaning/humor of this song/music video- Gangnam is a place for rich people in korea so gangnam style basically means "rich person style" (being cool and all that other stuff). So hes saying Oppan Gangman style which is saying that ur big bro / boyfriend (him) has gangnam style. The humor in the music video is that he does all these things that "rich" ppl do in "poor" ppl places. Ex- tanning in the park instead of beach, swimming in the spa instead of pool, and etc.
A very intriguing music video and good beats give this a good rating, but the obvious language barrier to relieve it of points. The video is well directed and seems to descend into an enjoyable sense of craziness as it goes along, and the beats really have this edge that makes one's foot start going with it. I've got a good feeling that if I were to properly understand the lyrics, I would probably get a good laugh out of it, with the general theme the video shows. A very good effort.