Pirate Admiral: Slaughter

A modern man who travels to the world of pirates obtains a system that allows him to kill others to gain experience points, increase his level, and strengthen his strength.

He became a navy officer, constantly eliminating pirates in the navy. He was promoted step by step, and his ultimate goal was to become an admiral.

During this process, he continued to fight against pirates and the Four Emperors until he reached the top of the world. What were his thoughts?