(Note: This battle has discrepancies between the manga and anime versions. The differences will be noted in full further below.)
so vengefully determined to make that happen to Lucy, she misses several vital clues that something is amissNana
After meeting the young diclonius, Mayu takes Nana to the Maple House in order to both get her something to eat and to glean more information on her and Nyu's connection, since they both have horns. Kouta is eager to know of the latter as well, and invites Nana in but struggles in opening the door. Though it's Nyu who's present when the door opens, Nana only knows her as Lucy and attacks her right away. Nyu isn't awake for very long, as the combined efforts of Nana's attack and a fever no one yet knew she had exhausted her.
Nana is immediately reprimanded by Kouta, who slaps her and demands to know why she attacked his friend. Nana insists she's done nothing wrong since Lucy is the evil one, but runs out of the house in anger. Further down the steps leading up to the Maple House, Mayu catches up to Nana to return her bag to her. The pair go to the Jizo shrine not far away, where Nana explains what Diclonii like her and Lucy can do.
When the two return to the Maple House a short while later, Nana comments that it's very quiet and that she suspects Lucy might've done something to Kouta and Yuka while they were gone. Before they can go inside, Lucy opens the house's outer gate to glower at the two. She knocks Mayu backward with her vectors and asks Nana if she came for a rematch, further taunting her that there isn't much of her left to cut off.
Nana succeeds in knocking Lucy back through the gate, where she hits the front door. Though stunned for a moment, Lucy stands up again. Nana fires her prosthetic arms at her, but Lucy's vectors knock them away as Nana closes in. As Lucy prepares to attack her again, Mayu intervenes by hugging her and telling her she can stop fighting if she wants to. Lucy pushes her aside and approaches Nana, but before the two can pick up again, Mayu again interrupts and begs Lucy to stop fighting. Lucy winces and hunkers to the ground as Nyu again takes over. Yuka and Kouta then arrive, with Nyu tearfully hugging Kouta. While the two are preoccupied with Nyu, Mayu tells Nana to put her prosthetic arms back on before they notice.
- Though Lucy does wake up in the manga, she never goes outside to fight Nana. Instead, she's forced to stay in bed by Kouta since she's got a heavy fever. She reverts back to Nyu without incident, and Nyu later forgives Nana on her own volition.
- In the manga, the events play out differently. Instead of appearing at the door, Nyu pops up out of a hall closet with the intent to scare Kouta. Nana's subsequent attack sends her through the wall instead of knocking her further back into the foyer and breaking the door in the process.
- Nozomi is present for the attack only in the manga, since she never appears in the anime.
- In the manga, Nana runs away to the Forest Rest Shelter rather than taking Mayu to the shrine.
deciding in that moment to keep watch over a fluid if not chaotic situation with NyuNana