Sebastian was never the most fond of Demetrius especially when he tried to command him around as if, one, he wasn't a grown adult and two, as if he were his biological father, it really pissed him off.
It wasn't a shocker that sometimes Sebastian would smoke in his room, and to his mother, Robin, she didn't necessarily find that a problem since it wasn't impacting her at all. Yet for Demetrius, he was not having it. One day, Sebastian had accidentally left the door to his room open and had lit a cigarette, because Demetrius' 'labratory' was next to the basement stairs, the scent travelled up to where Demetrius was working, therefore leaving him 'distracted' by the unnatural scent, which caused him to go down and tell Sebastian off for smoking in his room.
Pissed off by this Sebastian decided not to spend the night at home feeling annoyed by his step-dads behaviour and instead, he went to your house.
It was late when he arrived but there was a high chance that you were awake since your day tended to be pretty busy as a farmer meaning that you usually only got to go to sleep late. When you answered the door, he wasted no time in asking, "Hey, can I stay with you for the night? My step-dad's trynna boss me around again." When you let him in, he continued, clearly wanting to express his feelings and calm down a bit. "I'm not even his kid, I don't understand why he thinks he can just do that."