This is so wonderful in so many ways! The manuscript-style color-plate, and the snowy night atmosphere, and the intimacy of their closeness, and hands together on the sword, and the fantastic expressions.... there's more but I'm a little dazed!
I particularly love Snape's expression. You've managed to convey that special protective, mentor quality. I think it may be in the watchful look he has, like he's aware of their surroundings while Arthur!Harry is so enraptured by the sword. It all seems to imply that Harry is cherished and their relationship is very deep. Its a story in itself!
I also adore the choices you made for their attire. You paid so much attention to the fabric-y-ness of the robes and garb. I just want to get in there and touch everything and see how its made! Snape's green robe adds so much depth to the scene too, and looks so warm and soft. I'd really like to feel that one! (I'm a costumer. Can you tell?)
This is completely fabulous and perfect. I think I'll be looking at it for quite some time.