When Sirius' imaginary friends follow him into adulthood, he's fine with it. He knows it's anything but normal, but he's still fine with it. It's always been like this. His imaginary friends were beyond peculiar, but he'd grown used to that as well. They'd talk to each other. They'd hold conversations, they'd have arguments and epiphanies and crack jokes like it was normal. It was, wasn't it? After all, these were his best friends.