Luciole wa Yume wo Miru

Awakened by a radiant light, Luciole realized he'd been asleep for a long, long time. Stretching to the horizon before him lay an abandoned world. Whatever life had once taken root here was long gone, leaving Luciole all alone—except for Claude. Now, with a self-proclaimed five-hundred-year-old archmage for his only companion, Luciole will set off on a journey to discover how alone the two truly are.
(Source: Yen Press)