The flames chase up the walls remarkably quickly, chewing through paint and brick and wood. There's just enough of the walls that counts as flammable to feed into it easily, and Tim has to duck his head and yank up the neck of his pale shirt to breathe through the fabric as the smoke starts to spill out in thick black billows.

He races for the door, but doesn't yet start to hammer at it with clenched fists. If he had his window, he could have escaped that way. If he starts screaming and throwing a fit, they'll know it was him. They'll know why it started in his room.

So he has to wait for the fire to start to eat into the other rooms.

Even if it means he's still inside it when it all goes up.