A whipping boy was a young boy who was assigned to a young prince and was punished when the prince misbehaved or fell behind in his schooling. Whipping boys were established in the English court during the monarchies of the 15th century and 16th centuries. They were created because of the idea of the divine right of kings, which stated that kings were appointed by God, and implied that no one but the king was worthy of punishing the king’s son. Since the king was rarely around to punish his son when necessary, tutors to the young prince found it extremely difficult to enforce rules or learning.
Because the prince and whipping boy grew up together they usually formed a strong emotional bond, especially since the prince usually did not have playmates as other children would have had. The strong bond that developed between a prince and his whipping boy dramatically increased the effectiveness of using a whipping boy as a form of punishment for a prince. The idea of the whipping boys was that seeing a friend being whipped or beaten for something that he had done wrong would be likely to ensure that the prince would not make the same mistake again.
通常whipping boyが唯一の王子の友だちになるので、深い絆で結ばれるらしい、なので自分のせいでwhipping boyが苦しむのを見ると心理的に堪えるのだそう。うーむ、なんかイギリスっぽいというか、陰険というか、この制度を考えた奴は凄い。