Original title: Pure Marriage ～赤い糸物語 さくら編～
Aliases: ぴゅあまりっじ, Pyuamari
Since a few years ago, Touma’s imouto Sakura had become extremely cold to him, treating him almost like a stranger. However, her true feelings became clear when he was to choose either Madoka or Celica as his bride. Realizing his own feelings, Touma chose Sakura as his bride, to her great excitement. With the help of Rudman, they were able to live openly as a couple while being siblings and students. It was the beginning of a married life with a tsuntsun yet doting imouto. One day, Sakura suddenly said that she wanted a baby… not in the future, but right now!