Plot
A virgin girl named Mamori who arrives on an island must compete in battle using special powers only activated through her sexual activity with the other girls on the island.
Where to watch Valkyrie Drive: Mermaid?
Valkyrie Drive: Mermaid is an action show featuring Yuka Iguchi and created by Yosuke Kuroda.
Valkyrie Drive: Mermaid is currently streaming for free (ad-supported) on Tubi TV and it's also available on Crunchyroll, Crunchyroll Amazon Channel and Funimation Now.
It is also possible to buy Valkyrie Drive: Mermaid on Apple TV.