Honestly, I am surprised that this one isn't more popular. Writing quality is top-notch. Some rare typos and the occasional forgotten word but honestly, which story from a hobby author doesn't have those?
Story development is solid. We get an active childhood with training and interactions that isn't needlessly prolonged. His mid and later teens are what's written about at the moment of the review and it's been... eventful.
Character Design. We have an MC who is kind of a loner, pretty smart and has a good and feasible growing speed for someone who knows what he's doing.
The female lead is a damsel in distress with a trauma who shows yandere tendencies. She also isn't a virgin and not by choice. That seems to be one of the main reasons for many to drop the story but as a female 'slave' to savage pirates, it is realistic. For those who can't stomach stuff like this, the story may not be for you, but do know that traumatic thongs like this happen everywhere. You don't want to know the real number of r*pe victims as most never report the case because of shame.
Updating Stability. Well sometimes we get more, sometimes a bit less, but the chapters have a decent length. Of course, we won't ever be truly satisfied but it's nearly enough to tide us over.
The world background is One Piece and it's portrayed pretty well. Nuff said.
My conclusion is quite simple: It's a good story with a decent pace, interesting action and hopefully wholesome romance in the future.
Well done!