Plutonium

hello , please anyone can tell me if there is any illegal issue like thiefty or piracy if i use plutonium ? because i don't purchase the game ( cod bo2) from steam and download it for free from plutonium
thanks

hello , please anyone can tell me if there is any illegal issue like thiefty or piracy if i use pluonium ? because i don't purchase the game from steam and download it for free from plutonium
thanks