Wow. That ending was too perfect with the letter and the drawing, Brian waking up in Justin's bed but sneaking out before he wakes up...

And these few lines I loved:

Justin's asleep, and the only part of him that's visible is a shock of blond hair at one end and a foot at the other. Everything else is effectively buried in a cocoon of covers. Brian watches the slight rise and fall of the bundle as he strips off his clothes and attempts to find a way inside the warm, disordered mess.
...
The sheets are scratchy, the mattress is lumpy and there's only one pillow, but those thoughts vanish almost before they form as Brian finds himself with an armful of sleepy, warm teenager.