According to more recent trivia, Doraemon’s blue color comes at the cost of many tears. In a more recent anime episode, it’s shown that his yellow paint flaked off soon after his girlfriend cruelly laughed at his perfectly round face. Doraemon tried to be resourceful and lift his spirits in the wake of her laughter using a quick and easy dose of “the source of happiness.” However, he made a mistake and accidentally drank “the source of tragedy” instead. The resulting tears shook Doraemon’s body so hard that all of his yellow paint peeled away, revealing that familiar blue color underneath.