In an alternate universe where Sirius Black never went to Azkaban, Harry divides his life between the Dursleys' house and Mr. Black's bookshop -- until Sirius realises what the Dursleys are doing to him, and takes him away from their care.

Only Severus sees what's really going on here.

The first time he picked up Gryffindor's sword he had been young and terrified. The second time he fumbled the hilt, he had still been young and he had still been terrified. The third time? He was not much older and no more prepared for the world he had just entered, nor for the enemy he will face in order to win this twisted game of life and death.