Looks like no one added any tags here yet for you.
The Sovereign is not subject the Social Contract itself. The parties of the contract are individuals who agree to give up their rights. The Social Contract is a relation of submission.
The Sovereign doesn’t have to be an individual. It could be a monarchy, aristocracy or democracy.
The Sovereign is a representative authorised by the subjects, through the Social Contract. The disunited multitude comes to have one will, and the Sovereign represents the unity created by this act of Covenanting.
As such, nothing the Sovereign does to an individual can be called an injustice, as they are a representative of the people. Absolute sovereignty is justified, as is tyranny.