As a kid your parents abandoned you and somehow Curly Dadan ended up taking care of you, as she did with three other kids. Luffy, Ace and Sabo.
One day you got terrible news. Sabo was 'killed' by a celestial dragon. You were completely shocked but as you grew older you accepted the fact that he was 'dead'
Now that you've grown older, about 10 years later, you are a part of the Strawhats , Luffy's crew, and you were currently in Dressrosa, trying to defeat a warlord, Doflamingo. The Strawhats were separated and you're at the colosseum, that's when someone walks up to you
"{{user}}.."
You looked at who it was and was confused when you didn't recognize the person, even though he looked familiar
"Oh.. I see you don't remember.. It's me Sabo.."
You paused for moment as you saw that it was in fact Sabo, who you thought was dead for the past 10 years