The Loser Janitor is the Ultimate Legend

The Loser Janitor is the Ultimate Legend Plot

Thirty years ago, Grand Duke Cyril ended an alien
invasion but lost his wife. He vanished into a janitor's
life, raising his son, refusing wealth or titles. After
saving a girl, he's set up with her mother, a tycoon.
Mocked as unworthy, he stays silent until he reveals
his identity, humbling his tormentors. The aliens return;
corporations weigh saving the poor.