Karen Yuzuriha designs bras, panties, garters, and more for a luxury lingerie brand, and she refuses to approve a prototype without trying it herself. Male employees become her test subjects during fittings. She performs endless trial fucks, gives tighter titjobs than a bra would normally allow, pulls panties aside so the fabric rubs during penetration, and tests revolutionary lingerie designed to stay clean even after a creampie. Armed with huge breasts, beauty, and filthy inspiration, she devours every man around her.