death walks

in a world where when you die an reaper condemns where you'll go in the after life, and so on that's were the souls follow certain death there life's flash then its over, but every so often a few demons make some deals and angels get greedy with their humans the deals they make can get them stronger. the royals know as the fates, death's and gods they watch over who gets certain souls to save main or bring to the white gate. the 3 main daughters of death are royalty they are never allowed to make deals, until they are certified grim reapers but what happens if the youngest falls in love with a certain deal making demon?