Эпизод 13

The opening is the Gremory group hunting a rogue devil named Maverick. After sending him to stand trial in the Underworld it's discovered that he was working in a lab developing Chimeras. The next day while Issei is wondering about Maverick's parting words he overhears how many of the school girls are getting sick with anemia and who all possess the same characteristic. Finding the source of the illness, Issei wants to protect it upon finding out its special ability, which also infuriates Koneko.