I Became a Boss by Cultivating Demons

I dressed up as the most useless demon cultivator in the cultivation world and was laughed at by everyone. Everyone in the division thinks that I am the bad guy. Until the battle between immortals and demons, the righteous Supreme Being was injured and the Demon Lord fell. When everyone was in despair, I took off the mask I had been wearing for many years. "Sorry," I smiled slightly, "The Demon Lord you are looking for is actually me."