OMG? The Janitor is the Martial Lord!

He vanished as the Martial Lord. For three years, Skyler Carter hid his power. Now his sister is losing her fight and their dojo faces ruin. When his secret aid fails, he must unleash his sealed strength. But the real enemy is the Luminary Society, kidnapping warriors for cruel experiments. As the final battle nears, who will survive the legend's return?