Diamond Dresses are the highest rarity Aikatsu cards in Aikatsu Friends.They are similar to Premium Rare dresses in the original Aikatsu! and Aikatsu Stars! . Diamond dresses are worn only by a Diamond Friends pair, like Love MeTear consisting of Karen Kamishiro and Mirai Asuka.
Note: Premium Rare dresses still exist in the AiFure universe, however, Diamond Dresses are of an equal status in rarity. Diamond Dresses can be worn only by Diamond Friends, however, Premium Rare dresses can be worn by any idol.