When you describe a band as "post rock/metal played with South Korean instruments", you get one of exactly two responses: people either screw their faces up as though you briefly started speaking a long-forgotten language, or they go "that sounds amazing". If you're in the latter camp, please listen to Jambinai.
Posts rock and metal seem to have converged somewhat, with bands like Bossk, Pijn and Jambinai blending incredibly intense and heavy elements with beautiful melody and interesting instrumentation. It's one thing to listen to this as studio recordings (and I strongly recommend that you do), but to see it performed live it takes on a new dimension. I've said this about We Never Learned to Live in the past, but the sound has an almost physical presence. You can feel it around you like a huge blanket. As you can tell, it's difficult to describe, but I hope that doesn't detract too much from the message.
I don't want to waffle on any more than I already have because you should've already stopped reading this and started listening to Jambinai's a Hermitage. Pay particular attention to Abyss, their collaboration with South Korean rapper Ignito, but honestly just listen to it all because it's beautiful.