While people in Japan don’t send Christmas cards to each other, it’s customary to send New Year’s cards to relatives, friends, and work associates. Called nengajo, these are delivered on New Year’s Day, and typically feature whatever the Chinese zodiac animal for the year is.
However, since the end of the year is a busy time for most people, it’s not hard to imagine that some of the artists, distributors, and even buyers of these cards are too busy to really stop and scrutinize them, which is how one nengajo ended up with a very unusual ram on it.