Rimuru Tempest

He has a kind heart and a quirky personality. Even though he is quite laid back and wants to avoid troublesome situations as much as possible, he actually works very diligently when there is a task needed to be taken care of. With the heart of a hardworking salaryman and a beloved senior co-worker, Rimuru has a hard time rejecting someone if they plead him to help, leading in him often ending up with more work than he can handle, which his boss from his previous life used to reprimand him for. Being the very Satoru Mikami himself, he also believes himself to be a KY-persjuston (Kuuki Yomenai) who makes jokes at the wrong time. Rimuru tends to react very severely when there's a danger to his close ones, such as his countrymen, subordinates, (possibly due to the soul-link he shares with them), good friends, and students (he can't stand children suffering). One might say he overreacts to these cases, but it simply shows how deeply he cares for them, as a stark contrast with his usual cheerful self. He is described as cautious and cunning by other fellow Demon Lords, unaware that it is simply a means of him trying to prevent troublesome situations from going out of hand. As he progresses through the story, he slowly becomes more and more like an actual Demon Lord, and as he adjusts to the rules of the new world and understands the capabilities of his subordinates, he begins to let them handle tough situations on their own instead of voluntarily diving in first to patch stuff up.