There lies a city on the fault line between Heaven and Hell, Daten City, where humans live under the constant threat of attack from evil spirits. Darkness invades peoples' hearts, and not one person realises that it is consuming the city... There are those who seek to obliterate these manifestations of human desire with transcendent light. Has the duty of repelling the darkness fallen to the messengers of God or the servants of Satan? — from intro

Panty a teen-celebrity-like sex-crazed blonde-haired girl and a her sugar-addicted black-haired Goth Loli sister Stocking are kicked out of Heaven for their misdeeds there. These two angels now have to battle Ghosts on Earth for Heaven Coin, to pay for tickets back to Heaven.

"Do the angels bring tidings of hope and light? Or do they bring despair and darkness?" Better bet on the latter!

[Source: AniDB]