While I was there, I was introduced to Compose Coffee by my friend. It's apparently a chain in the south, I have yet to see a location in Seoul.
The coffee shop is decorated minimally, but yet still looks quite modern and clean.
The claim to fame is the fact that the coffees actually taste like coffee and they have this crazy deal. If you order a beverage "take-out," you get a 1,000KRW discount and a size upgrade.
The menu is quite extensive, actually. I decided to go with a Cafe Latte, 2500KRW after the take-out discount.
The service is prompt and friendly.
The discount makes and Americano 1,500KRW, which is ridiculous.
Best of all, you don't have to pay extra for iced beverages, which will definitely be great in the Korean summer.
They also have "real strawberry milk," which looked quite nice, but I'm still slightly partial to the one at Geurida Kkum.
If I lived closer, I would definitely frequent Compose Coffee more often.