I been for a thinking for a while and I couldn't decide how old is Mary. If anyone know her exact age, please tell me her age. Remember her grandmother is also know as Medusa in Greek, and Mary is in the modern age. Wait also include her family timeline also and good luck answering this.
According to this site: http://kagerouproject.wikia.com/wiki/Marry_Kozakura she is 140 years old, but I have never gone beyond episode 2 of this anime, so I don't really know.