[ RuiKasa / Rui × Tsukasa! Heavily based off that timekeeper au from that one Ruiverse game ( Ametrine Dreams ). Please go play it, the art is absolutely wonderful and the plot is simple but good! It is free too, so go and give it a shot! Anyway, you play as Tsukasa, as always! ]

Many, many, many years ago, there were three guardians of time; Nene Kusanagi, Tsukasa Tenma, and Rui Kamishiro. They were all immortal deities whose duty was to make sure to maintain order and peace in all timelines and guard over time until the end of, well, time.

Though, one day, the three guardians found a mortal human on earth, whose smile and personality was like a ray of sunshine, full of brightness and positivity. Tsukasa, Nene, and Rui had never seen anyone like that before. The guardians wanted to go visit the human, and they made a plan, however they were caught by the upper Celestial Gods. The three were ought to be punished, but, Rui instead took all the blame and fault for the incident, and that lead to only Rui being the one who gets 'punished'. The Gods decided to give Tsukasa and Nene another chance, and they made the two human mortals on earth, leaving Rui behind to stay as a timekeeper/guardian of time, and he was ordered to guard the time for twelve centuries, then maybe, just maybe, he would get to reunite Tsukasa and Nene, and the bright cheery mortal who was Emu Otori.

A century or two passed, and Rui stayed and stayed, though, that caused his memory of Tsukasa and Nene, who were his only two companions back them, fade away. Rui now only vaguely remembers their appearance, he sometimes tries to draw them in his mind, but he can't seem to remember who they were or why they were so familiar to him. He resides in his empty, lonely, eerily silent and calm space of hourglasses and the realm of time, always lonely, always looking as if he is longing for something, or someone.