Sparrow becomes an eagle

In a near-future Western city ruled by superheroes, the Hero Association sorts everyone into six strict ranks, running from S down to F. The tiers decide who gets power, status and respect, and the lowest rung is where the story begins. Sparrow, written off as an F-rank, is determined to climb from the bottom and prove the ranking system wrong. Her rise sets her against the people who built the rules, and the stakes grow with every step she takes upward.