She was death on legs, a killer and a goddess, and he was in love with her just as much as she was with him. That's what made the time less painful as it passed by; each day without her, even as the hole in his heart festered with emotions he couldn't even begin to fathom, was a day that allowed the ache to become less. He pined and was in pain, but that pain sharpened so that the wound might stay fresh. For ten thousand years, all he did was lay on his back and stare at the cell phone that had once been his Future Diary. His Random Diary. It made him feel anger, and hatred, and grief as well, but he couldn't have taken his eyes off of that last sentence even if he wanted to.
Muru Muru did a fantastic job of staying quiet for the first decade, allowing him his thoughts, but she became more and more aggressive in her speech as time wore on. He'd taken a trip down to the earth a few times, hoping that traveling around the causalities of time and space might aid him in throwing off his grief, but he knew all along that it would be nothing more than a futile gesture; he was the God of Time and Space, and knew all things. All that time's passage did for him was increase the weight of love's lodestone upon his heart and mind, and he hated it with a loving passion.
There were times when he looked into the Third World, naturally, and he certainly enjoyed what he saw; his Third World self was in love with some girl or another, though he couldn't remember her name. The Second of the Third World grew up with loving parents, though he dared to look no further than that lest he pain himself more. The Third was defeated by the Twelfth, though both of them ended up in jail after the Twelfth tried to kill an innocent. The Fourth's son lived, and the Fifth was never introduced to the strange cult that used the Sixth as a figurehead. The Sevenths got married in the tower, just as they'd always wanted, and that was all he needed to see for them to know that they were happy. The Eighth received regular donations from the Eleventh, who never invented the Future Diaries in the first place. The Ninth from the Second World lived out her life as the wife of Nishijima, though her Third World counterpart wasn't so lucky...unless he missed something after leaving, of course. The Tenth spent time with Hinata and his estranged wife, growing closer to them until they became a whole family once again. All in all, everyone got their happy ending.
Everyone, that is, except for him.
For ten thousand years, he allowed the Second World to govern itself while he wallowed in misery and no small amount of either self-pity or self-loathing. Muru Muru told him that no god should act as such, especially not one that had complete control over almost everything, but he just couldn't find it in himself to care. God was dead, and he'd killed him...or, rather, his love had. She'd taken her knife and killed herself, because that's what it took for him to win, but her death had been pointless. She might as well have simply killed him, because her death had the same effect on him as his own might have.
For ten thousand years, he allowed himself to waste away under the unwatchful eyes of himself. Then, for the first time in a hundred centuries, he heard a noise that he'd thought to be long forgotten in the distant past. It was the one thing he'd always dreaded, but now he couldn't wait for it to finish: static...which meant the future had changed. More than that, however, it meant that he'd been wrong about something. When he looked at it, as it cleared, he barely contained his shout of joy.
The Second stabs herself and dies. It had read. The six words had haunted him for an eternity in his hellish limbo, but they had been replaced by a separate six words entirely.
Yuno came to visit me today. It read. As he looked up, he understood that the First World's Goddess of Time and Space had not been killed; she hadn't been in her own dimension, so it was impossible for her to not survive...but it had been enough to fool his future diary.
All it took to convince him of the truth was a single word that nobody could have produced except for her, and he knew himself for the luckiest person to have ever lived...having become the master of all things in time and space, he knew that such was already the case, but that didn't matter. She was here, with him.
Tell me that you still recall my name...Yuno-chan.
"Yukki..."