Zeno Renora

Born on Minion Island, both of his parents were enslaved to a pirate crew. They weren't part of the crew but forced to work under them, so they were on the sea a lot. His family was one of ten, each allowed one child and we're assigned a number at birth. Zeno was number zero, the child that the pirates kept away from the rest, even his parents. Eventually, the parents had died, leaving the children to work for their captives in their place.

One day, while being fed, one of the pirates accidentally gave him a devil fruit along with his meal, thinking it was a regular fruit. Zeno ate it and learned how to use its power to fight off his captives. He was 12 at the time. But before he could do it himself, the Marines beat him to it.

They were saved. Or so they thought.

The Marines slaughtered the pirates and the other children, thinking they were also pirates. While they were doing this, Zeno was hiding in a small boat, watching this go down. He lashed out in a fit of rage but wasn't able to do much. He was able to kill one grunt and injure another before he escaped with deep gashes and a missing toe. He was 14.

He managed to reach a small island that was under the Revolution Army's control. They tended to his wounds and he ended up living there until 18, which was when he joined them. Thinking that they can utilize his devil fruit, he has bumped up to Revolutionary Commander soon after.