The keeper of night

"Ren Scarborough has been collecting souls in the London streets for centuries...When her failure to control her Shinigami abilities drives Ren out of London, she flees to Japan to seek the acceptance she's never gotten from her fellow Reapers. Accompanied by her younger brother, the only being on earth to care for her, Ren enters the Japanese underworld to serve the Goddess of Death, only to learn that here, too, she must prove herself worthy"--.