Once you get to the compound, look for a photobooth with a red curtain. It's a secret passage to Int.Bar, a retro-themed speakeasy that serves delicious, one-of-a-kind cocktails. Try the "La Dolce Vita", an absinthe-based cocktail inspired by the namesake film.
Our Airbnb was in Hongdae, a young, hip area that's alive every night. There are plenty of shops, restaurants, and places to grab a casual drink. I loved just strolling around—you're bound to discover some aspiring artists busking along the way. PS Don't sleep on the street food carts. We stopped at one as soon as we arrived from the airport (luggage and all), and it was one of my best meals of the trip.