Flandre Scarlet in Arknights

The girl from the Scarlet Devil Mansion meets a soul from another world, and the two souls merge into one, creating a new Flandre with a brain and reason. After stepping onto another world called Terra, she looked up at the twin moons in the sky. "Ugh, I want to go home so badly, I miss the desserts my sister makes for me..." And so the girl embarked on her journey to find her way home. — Description from novelcodex.org