Talking to Candyboot will prompt him to talk about one of 15 different topics. Some of them will differ depending on if you have completed certain sidequests.
He has a small part in the sidequest "Lost sword". You are asked to talk to Candyboot at one point, about information on a stolen sword.
He also has a small part in the sidequest "Beer and more beer" where you simply buy a beer from him, wich is the only time in the game you actually buy a beer at any inn.