I played the Sora arc when it was finished by this same translation group. Good stuff. Probably THE definitive twincest eroge. The art is wonderful and the incest angle is compelling and dramatic, not simply crammed in there to check a feature box like you see in most games. My one complaint is that outside of the interactions between the two twins the setting and characters fall flat--nothing you haven't seen many times before. Sora and the protagonist have a special relationship, and unfortunately I hear this fades into the background in the other arcs to give the respective heroines their time in the spotlight. It would've been more interesting for Sora's jealous possessiveness in her arc to creep into the other arcs as she competes for her brother's attention.