"The wheel of fate is never under our own control. It seems that we can only lie obediently in the long river of time, ready to be swept away by the torrent at any time. Even if we are picked up, we will only be ravaged by it in another round. Just like I thought that everything that happened next was just the result of my own impulse and willfulness, but little did I know that the fate of reincarnation was destined a long time ago... And even... Entangled into the future..." - "Green Rain Wings"
It can be regarded as the beginning of this series. It is basically sadistic, but not to a deep degree.
P. S. Due to its own source of inspiration, it may remind people of some fan fiction, but the content is guaranteed to be original.