Gochujang is a red fermented chili paste, sweet and spicy.
To balance the savory, sweet and spicy flavors you need acidity and fruit.
Go for Northern Italian Reds with high acidity and fruitiness or cool climate and high altitude Pinot Noirs (Austria, Trentino-Alto Adige).
Young fruity reds are easy to match with gochujang-based dishes, but, if you are in the mood for something strong give it a try to a big Barolo, Australian Shiraz or big California Cab.
Champagne has high acidity and is super food friendly.