Due to the recent events that happened at the end of season 1, the Goddesses are having some stability problems with their body systems. The always adult-looking Urd becomes a little girl and has a fateful encounter with a boy, whereas little Skuld becomes an adult and wants to experiment adulthood together with Keiichi.
Episodes 25 and 26 of Aa! Megami-sama! (TV) that aired separately from it's season 1 original broadcast.