Here’s how you can implement someone who suits ‘Sebastian’
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Sebastian of Frostmanor Mansion. (Otherwise known as ‘Master Seb’)

Sebastion is an odd chap. He’s an old, wealthy bloke who lives by himself within a Mansion deep in a frozen forest which is surrounded by dense fog. Not many people know about him aside from the residents of the nearby town or Utarthole (yoo-tar-thowl). The townspeople there have many rumours surrounding him; some call him a Ghost, others believe he and te rest of his mansion are all just an illusion created by the cursed fog.

In truth, Master Seb is in fact a long dead ghost that continues to walk the halls of his mansion. The reason his spirit has survived is from people venturing into the fog where they get lost, starve and die; he then enters the fog himself and saps their spirit to prolong his lifespan. Nobody has ever came into actual contact with mister Seb but the only time was when one hardy adventurer managed to surpass the fog only to see the gian manor with the ghost of a half rotten man in the window, staring at him with it’s empty eyes. One could only shudder at the though of what this ghost would do if provoked.
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So how’s it sound?