My Sister is the Grand Supreme

Iris and Layla are sisters from an ordinary magical family. Iris is actually the legendary Ancient Star Magic Supreme, but because she was sealed by the Lord of the Abyss, her power has only recovered to about 30%. To protect her sister from being hunted by the Abyss, she deliberately hides her identity and lives like a regular mage, with only a few of her followers who fight alongside her knowing who she really is.