The office queen of karaoke meets her match when Retsuko's favorite band reunites for a special concert. The Brides of Resonance return, but why do they want to take over the karaoke bar? Retsuko and friends have to fight for their right to party in a METAL vs. METAL vocal battle that pits Retsuko against a shadowy enemy. Will Gori survive a night of metal and moshing? Is Haida truly in love? Find out in Aggretsuko: Little Rei of Sunshine!