One Piece: The System Only Activated When I Was 100 Years Old

He transmigrated to the world of One Piece, and he even came with a system.
Ron felt that he would soon be like the protagonists in various novels, crushing all obstacles and quickly reaching the pinnacle of life.
However, the system seems to have a bug and cannot be activated for a long time.
Fortunately, Ron is from Earth and knows about the characters and plot developments in One Piece.
So, in the time that followed, he adopted a little kid in this world, and that little kid's name was Monkey D. Garp.
After joining the navy, he became sworn brothers with another marine from the same period, whose name was Sora.
Subsequently, he took on several apprentices in the navy, who were named Sengoku, Zefu, and Tsuru.
A hundred years later, when the still-young Ron was training his great-grandson Monkey D. Luffy, he finally realized that his body had been completely eroded by time.
Just as he was preparing to accept that his life was coming to an end.
The system that had been running for a hundred years was finally activated.
Looking at the first task that popped up on the system, Ron couldn't help but complain.
"No, I'm already a hundred years old, you want me to be a general?"
This book is also known as "One Piece: I'm a Hundred Years Old and You Still Want Me to Be an Admiral?"
One Piece: I've been in the Navy for a hundred years, you think you can compare my background?

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