The background and foreground elements just look lovely. I wish I can draw something like that. The characters always look off when I try and place them somewhere. Must practice some perspective! And Snape, guh. Let me love you. I love seeing arts where Snape is "casual," not something like wearing a t-shirt, but like this, with his sleeves rolled up for some brewing or something. Lovely job ^^
It's very 'green'. I like it. All those potion bottles must have taken ages, though. I like how Severus has no turmoil here, he's just checking out potions. Getting in touch with his geeky side, I guess.