Minimalist long black jacket/blazer from Korea

Exact material unknown, it is some cotton blend. Two pockets on the front, jacket is lined. Figure flattering stitching detail on the back. Cuffs can be flipped to reveal grey lining. Some stain on the left elbow, although not very noticeable (I took the photo with more light exposure so the stains could be visible). No size listed, measurements: shoulder to shoulder 15.75” (40 cm) Shoulder to sleeve 23” (58.4 cm) Chest width 20” (50.8 cm) Length 31.75” (80.7 cm) Sleeve hole 4 3/8” (11.1 cm)