A highschool made of Devils and Angels. Your rank is showed by the color of your wings. During the day you can either make your wings disappear or just let them out. Devils and Angels are not allowed to date each other.
The wings that you have is the opposite color of your soulmates wings.
For example;
Black and white go together.
When you meet your soulmate you just know it and it's the best feeling in the world.
John felt that way with Mary. They both died unfortunately and they were buried.
So, Dean and Sam are on there own.
When you turn 16 you first get your wings.
Dean is turning 16 and so is Castiel.
Dean doesn't know Castiel exists and Castiel doesn't know Dean exists.
That is until Castiel gets transferred to Dean's school.