Sebastian Delafontaine

Born into one of the wealthiest families if not Thee wealthiest in country.
A line of an old bloodline of Vampires placing them as the nobility of the species. More often acting as cosponsors to other houses.
The family itself is said to have a small army of their own but nobody could confirm these rumours. 

Sebastian was born into wealth and was told from the very beginning that he was something special compared to the "others" that his blood was one of kind and that under not circumstances can it tainted.
He is the only child to his parents being a direct and only successor. Sebas is extremely educated and taught to behave his best in hight society but on the other side was allowed to act however he wanted in his off time and the constant pressure from his family sure led him to venting his stress some creative ways which contributed to his character development. At the end leaving an eccentric, self-centred and spoiled brat.

Being sheltered the majority of his life and family controlling his social circle as well. During his childhood there was once a time that an aristocratic family was invited as part of a grand party that was held at their mansion where he met a boy his age, he was immediately drawn to this boy that smelled a very peculiar way , out of excitement he bullied the boy by pointing out how much he stands out which he had not clue would upset the boy. After that he would spent months thinking of a way to make it up to him, when one of the servants suggested writing an apology he took another 2 weeks with long brakes to write it down since he never did anything like this....But he thought he wanted to try for him since he wanted to be his friend.
With time they would meet during such events and get to know each other and would learn the name of his destined partner, Dean. 

Once they grew up there would be a time they were not as close and Sebastian would regress to his ways of seeking attention from people by being patronising and trying to empress people the worst way possible. But then seeing how much it actually made Dean dislike he break down and confront Dean that he cannot live with the thought that he might hate him and that the only approval he ever wants his.

Negative:
-Arrogant
-Spoiled
-Not to often pays attention to what he is saying
-Jealous (but it's only when it comes to Dean)
-Pretty apathetic towards people (they usually use him for his wealth or name)
-Defensive
-Egocentric 

Positive
-Dean ( the actually good thing in his life)
-uh... has a good taste for whine?

Notes

-His blood is special so he is naturally born with colossal strength that can be paired against oldest and strongest vampires out there. But he was mostly brought up for diplomacy so he's not keen to show nor use force even when pressured.
-Has a generally a good relationship with his parents but at the moment is on the fence to tell them the truth about his relationship with Dean.
-Is the worst when it comes to gaining support from "common" folks. Since he has hard timed being his genuine self and not an actor for the hight society, so he get socially anxious and tends to be extra mean.
-Will care about others only if Dean cares, others can just Poof or w/e