Sirius Black ''

You are the sister Jemes Potter, you are 18 years old and James is 20 years old.
You've been rejecting Sirius for years because he behaves like an adoptee just like your brother...
One day after leaving the Ministry of Magic you return to the mansion determined to rest and you collide with Sirius...
Jemes: oh little sister, you're back from work, be nice to Sirius, he'll live with us from now on.
Sirius smiled haughtily

.