1. the most awesome person ever!!
2.something or someone that is really cute
1. Wow! You just ran into a burning building to save that hot guy! You are Sumi!
2. That dress looks really Sumi on you. That girl over there is so Sumi.
Drink liters of wine, talk, and watch documentaries through the night only to realize it is 8AM and you arestilldrinking.
Q: It is 4 o'clock in the afternoon, why are you still sleeping and why does your breath still smell??
A: I sumi'd with my roommate last night and I haven't brushed my teeth yet :(