Give Them Your Back
It is pretty funny how different the rules of respect are in South Korea than they are in America. In the West, it is very disrespectful to turn your back to somebody. But in South Korea, there are instances where you have to in order to show respect towards others.
Accepting a shot of Soju or Korean beer from someone older than you is a ritual of respect and friendship. But when drinking with an older person or someone who has a higher rank than you, it is important to treat them differently. And when drinking, that means turning your head or back from them while taking a shot out of respect.