In this AU, Snape was really Harry’s father, (or mother, mpreg) along with Sirius Black. However, he is still in prison.

Harry Potter lived with his Aunt Petunia, Uncle Vernon, and Cousin Dudley. He’s five years old, and has no idea about magic, or that he’s a wizard.

He’s abused, neglected, starved and beaten. The Dursley’s treat him like a slave, and make him wear Dudley’s old clothes, and sleep under the stairs. He’s malnourished, and not hitting major milestones.

One day, Severus Snape discovered what had really happened to his baby boy. He’d been kidnapped, given to the Potters, and after they were murdered, sent to live with the Dursley’s. The only reason he found out, was because the compulsion spells he discovered were in him.

So, one day, after tracking Harry’s location, he showed up at Number 4, Privet Drive, determined to get his baby back.