Kenshin "Demon Lord"

About

In the East Continent, Prince completed a hidden quest and acquired Kenshin by helping take revenge for the death of Kenshin's lover. Kenshin is a level 100 sword master "self-aware" NPC. The name "Kenshin" (meaning Heart of a Sword) was given by Prince. Kenshin cannot level up.

(Source : Wikipedia)