Koumajou Remilia II: Stranger's Requiem is a 2D side-scrolling action game featuring characters from the Touhou Project, a popular franchise beloved by fans around the world, and a direct sequel to Koumajou Remilia: Scarlet Symphony.

A sequel to the previous game, Koumajou Remilia II: Stranger's Requiem is a significant improvement over the previous title in several ways, offering improved graphics and gameplay, an original story centered around a new protagonist, and a richer cast of characters. Embark on an adventure with head maid Sakuya Izayoi as she finds herself searching for a spring that has disappeared along with her friends from the castle.

Story
"No way! Back then, I'm sure Scarlet Devil Castle was......"

After the incident surrounding the Scarlet Mist covering Gensokyo, Sakuya Izayoi, the head maid of the Scarlet Devil Mansion, notices something else that is not right.

The people she called the family back to the mansion have disappeared, and an unwelcome guest mentions that "spring still hasn't come."

Sakuya immediately heads towards the site of the destroyed Scarlet Devil Castle to search for why this could be, but she finds a sight she can't believe, the castle standing there again...