1 definition by SeolSeol

He is very cheaky and never listens to the teacher. Although he is smart he likes being rude. He will stay like this until he is mature enough. When he is mature he will be a nice guy. He helps you with your homework and stay with you when you're sad or worrisome. He is a true friend and if you have a yeon su near you this will probably mean he is the only one. People are only rude to him if they are jealous or envious.
Girl: He seems so nice! What's his name?
Boy: Yeon Su
by SeolSeol October 8, 2019
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