Despite being very convoluted I thoroughly enjoyed the ending. Its fitting that one sibling can change the future and other one can alter the past. For once I see the ending couple as spot on, where in both timelines Riri and Tasuku go out together or one falls in love with the other. From what I see, the final ending shown was the last timeline in a long series that started well before the story began. It's really a unique story, that was pleasant (or rough) artwork, which was done a disservice by ending at three volumes instead of four. A shame there is no paperback english while noticeably worse work by this author does. Woe is me.
8/10.