Hyperdimension Neptunia The Animation: Neptune’s Summer Vacation is a oVA anime that premiered in summer 2019, produced by Okuruto Noboru.

About the production: the story comes from a video game, there is 1 episode of about 26 minutes and its current status is "finished".

Its main genres are action, comedy, fantasy, sci-fi and supernatural, with themes such as Primarily Female Cast, Alternate Universe, Female Protagonist and Henshin.

On AniList, Hyperdimension Neptunia The Animation: Neptune’s Summer Vacation has an average score of 69%, a good score, and appears on 5,128 users' lists.

The franchise continues in or follows from: Choujigen Game Neptune THE ANIMATION: Nepu Nepu Darake no Festival.

The first installment of the Neptune OVA Series Trilogy. Neptune and her friends visit "Watashi no Natsuyasumi Yama" (My Summer Vacation Mountain) filled with nature to enjoy their summer vacation. The four goddesses, who gather after a long time, are having a good time as usual. During the vacation, Nepgear and other sisters go to the mountains to wander around. After going through the stretch of a long torii (Shinto shrine archway), the sisters wander off into a different dimension. Then Nepgear meets a woman who just looks like her sister Neptune in her adult form. (Source: Crunchyroll)

Official synopsis from AniList.