Roselia releases the 18th single. "Steadfast Spirits" is written for the app game "BanG Dream! Girls Band Party!." Also includes "Shien," which is provided for #03 of the anime series "Cardfight!! Vanguard Divinez Deluxe Kessho Hen" as its outro theme song. This edition comes with a Blu-ray featuring the event "Roselia: Sei stark" held at Ariake Arena in June 2025.