Taiyo insists on returning to school. Nanao accompanies him by taking a drug to stabilize his body, returning him to his real appearance, a short boy with silver hair. Taiyo is surprised to learn in this body, Nanao attends school as a normal student, has several friends and even a crush on the head of the biology club, Rinne Kitasato. When Nanao starts to mutate again, he concludes that he must take a permanent vaccine that will mutate him forever. Taiyo stops him and endeavors to help Nanao himself with a tranquilizer gun. Kitasato's pet snake Basilisk eventually eats one of Nanao's drugs and mutates into a monster. Nanao feeds Basilisk his blood to safely return him back to normal. He then decides it will be best for everyone to stop attending school and mutate himself permanently. After Taiyo prevents this, they are seen by Kitasato, who convinces herself Nanao is capable of metamorphosis. She also forces Taiyo to join the biology club. Returning home, Taiyo and Nanao find Mutsumi, while attempting to make snacks to help Taiyo's Someinine Hyperactivity, has poisoned everyone. Nanao gets to work mixing an antidote.