The Paradise (Island) Forbidden ...on which people will DO THINGS to other people and forget wardrobe malfunction because there might even be some tonguing and it'll be like "Oh no, Neptune is so embarrassed~~"! (禁断の楽園（アイランド）……であんなとやこんなことやっちゃったりやられちゃったりでもしかするとポロリどころかペロリまであるかもしれなくていや〜ん ネプテューヌ恥ずかしい〜みたいな!, Kindan no Rakuen (Airando) ...De anna koto ya konna koto yacchattari yararechattari de moshika suru to porori dokoroka perori made aru kamo shire naku te iya~ n Neputyūnu hazukashii? Mitai na!), shortened as The Paradise (Island) Forbidden (禁断の楽園（アイランド）, Kindan no Rakuen (Airando)), is the eighth episode of Hyperdimension Neptunia: The Animation. It was first aired in Japan on August 30, 2013.
As Neptune eats her labeled pudding outside her place's balcony, Peashy points out that it should be hers. Trying to get the pudding, Peashy collides with Neptune, spilling the pudding in the process. Neptune scolds Peashy about her behavior and mentions that she hates Peashy. Not taking it so well, Peashy starts sobbing, calls Neptune an idiot, and runs away. After stating a remark, Neptune is surprised to see the other CPU and CPU Candidates from the other nations behind her. The latter points out Neptune as the "bad guy."
Inside, Plutia finds and comforts a crying Peashy by giving her a resembling doll of herself.
Vert, Nepgear, Blanc, Noire, and Neptune, all in HDD form, fly to R-18 Island with Noire and Neptune holding Plutia by her hands. Vert, Blanc, and Noire briefs Neptune, Nepgear, and Plutia about scouting for an artillery battery present that is detected by Lowee's satellites within the island. Plutia asks if she can transform, but Neptune doesn't want her to.
With the exception of Nepgear, the CPU Candidates stay behind in Planeptune, apparently not allowed to come with the CPUs. In the balcony, Peashy, who is holding a doll resembling herself and a Neptune doll, seems to be looking for something, and Compa and IF takes notice. Uni, Rom, and Ram also takes notice. When asked, Peashy denies and leaves the balcony. IF assumes that Peashy is looking for Neptune to apologize and make up with her.
Still maintaining their current forms, the CPUs change into swimsuits in R-18 Island due to its strict dress code. Vert stares and points out Plutia and Blanc's chest size and speaks her thoughts about how she wonders if the two will pass as adults, annoying Blanc in the process. Neptune settles the matter by saying that age doesn't apply to goddesses. Vert, Neptune, Noire, and Nepgear manage to enter the island without a problem, but Blanc and Plutia were met with resistance by the security interface due to their chest sizes. Irritated, Blanc destroys the interface to gain access. Inside, the group are back on their human forms, and they come across Linda, a supposed guide. The group recognizes her from before, so Linda explains that she's making an honest living. The group trusts her, so Linda leads them in a beach full of nude women, whose lewd body parts are covered by Mysterious Light Grasses. In order, Neptune, Vert, Plutia, and Nepgear disrobes their swimsuits and plays in the beach. Due to Blanc and Noire not wanting to strip, Neptune uses light grasses to make them look like they're naked and tells them to actually undress. Before Noire considers to undress herself, Blanc uses her weapon to create a wind towards the "nude" CPUs, exposing that the light grasses only create a mirage effect to make them look naked. Noire points out that she saw Neptune undress, but she reveals that it was only a mirage. Nepgear actually removed her swimsuit and accuses Neptune while feeling embarrassment. Neaby, Linda takes out a brown glass container object and grins.
The group eventually indulges themselves in activities. Noire and Neptune play volleyball, Blanc builds a sandcastle, Plutia builds a colossal sand version of a Neptune doll, and Vert spreads wax over Nepgear's body. Then Linda arrives with iced tea for the group. As Neptune takes the first drink, Linda smirks to herself. Neptune reacts after drinking and becomes embarrassed from others looking at her. Vert concludes that it might be due to a drug that maximizes shyness, so the group stares at Linda. Linda tries to deny that it might be her fault, but a drug container slips out from her pocket. Blanc tries to confront Linda, but a subtle but vexed Plutia gets in between them and reminds Linda that she was suppose to be an outstanding citizen. In reply, Linda states that she's a natural-born villain. Plutia transforms into HDD form and plans to teach Linda a lesson. Linda tries to run away, but Plutia catches up and punishes Linda.
In Planeptune, Compa, IF, Uni, Rom, Ram, and Peashy hold their own swimming party in a large swimming pool within the balcony. Meanwhile, Histoire answers a doorbell and sees who's in the door.
After being set straight, Linda shows the group the artillery battery. Neptune doesn't remember anything from what happened to her. Plutia says that Neptune was so cute, sending shivers down Neptune's spine. Arriving at the guns, the "artillery battery" is actually a huge bubble machine, blowing multiple amounts of bubbles. The bubble guns stop for a moment and aims in the air, leaving the rest wondering what will happen next, but it only blew more bubbles. Noire sees a momentary figure of Anonydeath before disappearing quickly. She dismisses it as her imagination and assures herself that he's in prison at the moment.
The guest is revealed to be a long-haired lady wearing a black suit. She waits in a couch, drinking tea, until Histoire arrives with Peashy, the girl she ask for and claims to be Peashy's mother. She accidentally spills her tea and apologizes about it. Histoire says it's no problem and momentarily leaves to get something to wipe it with. With Histoire in the kitchen, the lady takes out a capsule container and opens it in front of Peashy, releasing dark red energy that is absorbed by Peashy. Histoire comes back with a cloth. A blank-faced Peashy repeatedly calls the lady "Mama."
Neptune, Nepgear, Vert, Noire, and Blanc flies back to Planeptune. Again, Plutia is in human form and carried back by the transformed CPUs to their destination. They arrive back in Planeptune at night. Neptune shows the souvenirs she brought along, which are puddings labeled with her name to resolve the problem she has with Peashy when it comes to her puddings. Noticing that Peashy isn't there, Histoire informs her that Peashy already went home with her mother.
The lady arrives with Peashy in an apartment room. While the lady tries to ask questions, the place is revealed to be Anonydeath's, and the lady's name is revealed to be Rei Ryghts. Anonydeath stops Rei from asking more questions and states that she should only asks questions when there's a point in hearing the answers.
- The Hearts and Nepgear went to R-18 Island to scout it for an artillery gun.
- The artillery gun is actually a bubble machine.
- Rei Ryghts took Peashy with her and claimed that she is Peashy's mother.
The Hearts and Nepgear go to R-18 Island, a resort for adults only, to scout for the artillery gun present within. Meanwhile, the other CPU Candidates, Peashy, IF, and Compa hold their own swimming party in the balcony of Neptune's place. After taking Peashy with her, Rei Ryghts and Peashy arrives in Anonydeath's apartment.
Characters are shown in order of appearance.
- Rei Ryghts
- The end of episode 7 and this episode emphasizes this as a "fan service episode."
- In the dub, there are two references to lines from various video games:
- In one scene, as the CPU are flying back Plutia asks why they won't let her transform and references the line "Henshin-A-Go-Go" from the Viewitful Joe series.
- In another, when the interface grants Vert the access to R-18 Island, she says "All your boobs are belong to us", which is a reference to the infamous line from the game, Zero Wing.