@Panino remember he burnt his hand while grabbing the espresso/coffee back in cafe when he was with fourth year? Maybe that's why he has plasters. And about being grumpy, I don't think someone who lives with honesty would be happy when they are bribed and fourth year's sister tried to bribe him.
@Panino I read in the raws and the novel, SPOILER ALERT!!!! He got his hand burnt from coffee and fourth year gave him to croc bandaids. He likes them coz he likes fourth year. He is unhappy because he knows about the sisters situation with Suhan and he thinks they are using him as a buffer to protect fourth year, so yeah