"A few days after a mysterious group of mages attacks Kuou Academy, Issei and Ravel are hard at work hunting for a mage to make a pact with... But before they know it, they're once again thrown into the chaos of their daily lives! Amid the madness, Akeno uses a rare moment of respite to tell the story of how she first met Rias...a sorrowful, trying, and tender tale of their bond. Thus, a long-awaited mystery is finally revealed as the titillating romcom battle fantasy continues, and this installment is sure to be a heart-warmer!"--Back cover.