On February 24th, costumes of Nightmare members will be transformed into wearable items for your avatars with the help of JOYSOUND’s UtaSuki. This is their first appearance on this website. If you’re living in Japan right now, the site is accessible with your phone and you can download these clothing right on there for your own avatar.
Membership is free on JOYSOUND Avatar if you wish to Mea-ify your avatar.
Source: Nightmare OHP, JOYSOUND Avatar: UtaSuki