Choujigen Game Neptune The Animation: Nep no Natsuyasumi Hyperdimension Neptunia The Animation: Neptune's Summer Vacation
The Goddesses and their sisters take a break from the hustle and bustle of nation-ruling with a quick camping trip to "My Summer Vacation Mountain." When Nepgear, Uni, Rom, and Ram go for a walk, they pass through a series of shrine gates and...end up in another dimension?!
There they meet someone that looks like an older version of Neptune! What shenanigans will ensue, and can the sisters ever get back home? Are two Neps better than one?
[Source: Idea Factory Intl]