Oh! My Goddess: Flights of FancyAa! Megami-sama!: Sorezore no Tsubasa

The song may say "thank heaven for little girls", but who is college student Keiichi Morisato supposed to thank when three honest to goodness Goddesses move in and take over his life? After all, according to most mythologies, relationships between mortals and immortals usually leads to mortifying complications, so we're already talking about an extremely mixed blessing!