Anthropologie Holding Horses oversized dress

Tag says 0, but it fits very loose! I’m size 4 and it’s loose :) underarm measurement in the photo. It’s 34 shoulder to hem in the front, 38 in the back. I bought it from ‘we have one left’ rack, and there’s a little mark on the bottom (see the photo) It’s something that was left from trying on, not a defect, will come off after wash.