impassive; unmoved by joy or grief
On the surface he seems a stoic kind of character, but if you get to know him better you'll find that he's really a very sensitive soul.
dispassionate, impassive, imperturbable, stoic, stolid
Stone like: To be like a stone means you don't experience pleasure or pain. You are unaffected. STOIC sounds similar to TOY (if that 'c' is removed). a toy is impassive and unmoved by joy or grief