The Abandoned Town is a former modern residence of humanity before they deserted the surface for the plantations.
Before the arrival of the Klaxosaurs in 2037, humanity lived on the surface but the social status were segregated. The wealthy lived in tall skyscrapers, whereas the middle and lower class lived in smaller residences. When the Klaxosaurs appeared and caused destruction, APE introduced and led the plan to create the plantations, which required humanity to abandon the surface for security in the plantations.
For close to a century, the remnants of humanity never stepped foot outside or out of proximity of the plantations, and the children are never taught anything about the outside world. Squad 13 is the first unit of Parasites to be allowed outside the plantation for a vacation to the beach. They accidentally discover the abandoned town while exploring the area and find a mansion that has interior similarities to their boarding house, leading them to suspect it was used as an inspiration to build the environment they live in.
They also question why humanity abandoned the surface for the plantations and become curious of how society operates before the plantations. They all later sleep on the beach after this talk.
- The discovery of this town is the catalyst to how the squad learns concepts they were never taught and provoked them to rebel against APE.
- Ichigo finds out a kiss is a natural part of intimacy, which heightens her feelings for Hiro and makes her more determined to express her feelings for him.
- The boys realize there are more relationships other than partners, such as love.
- Kokoro finds the Baby Book, which makes her yearn to bear a child and pursue her feelings with Mitsuru, culminating in them forming a relationship, getting married, and conceiving a child but resulted in them being punished by having their memories altered
- Kokoro and Mitsuru’s memory alteration provoked the squad to rebel against APE and eventually this leads the war against VIRM, and the parasites achieving their freedom via Hiro and Zero Two sacrificing themselves to defeat VIRM.