Wardrobe/Costume Question

So I've been seeing this collection circulate throughout the vertical drama world and was wondering if anyone knew the company/designer who makes it? Or do we just think they're costumes made for the dramas themselves? 

https://www.imagebam.com/view/ME16UWGS https://www.imagebam.com/view/ME16UWGT https://www.imagebam.com/view/ME16UWGU