I know Christmas is over now, but it's still the season and it's fun to talk about. I can only think of two anime that are entirely, unashamingly about Christmas. There's Itsudate My Santa, which is an OVA based on a manga by Ken Akamatsu, the same author who wrote Love Hina and Negima, and the Satoshi Kon movie Tokyo Godfathers, which I guess isn't "about" Christmas per say, but it takes place on Christmas and clearly spreads traditional Christmas values. Other than that you usually just get a single, one off episode in a slice of life or romance anime. The romance one actually makes sense culturally because Christmas is seen largely as a holiday for lovers in Japan, similar to Valentines Day.

Voir le contenu lié