심해군주쿠키
오 이런 제품도 있었네요! 꿀템이네요
It's a product from Picasso's younger sibling(?) brand, and I think it cost around 5,000 won. You can use the black sponge to brush off powder eyeshadow brushes, and if you rub the brush with the purple matte like a washboard, the dirt comes off really well.
It's economical and great because it can be used almost semi-permanently!