To be clear, Valkyrie Drive, IIRC, is a multimedia franchise -- games, toys, manga, anime -- that revolves around teenage girls who turn into weapons when sexually aroused, and the other teenaged girls who have the ability to wield these weapons (read: fondle the other girls until they transform, and then keep them horny so they can fight with them).
So our heroes are a bimbo who turns into a scimitar when she gets horny and a mute autistic Cloud knockoff who can turn said bimbo on in order to use her as a weapon.
What's Rial voice?
A lesbian dominatrix who keeps a harem of girls that turn into weapons when they get horny, who she uses to enslave other teenage girls.
What about Marchi?
A lesbian who can masturbate to turn herself into a motorcycle.
Leah Clark has a bit role as a NPC.
Basically, it's something not unlike the Japanese version of My Little Pony / Teenage Mutant Ninja Turtles. A show designed to sell toys, with comics, video games, and the like all revolving around it. They do these every few years.
However, this one got banned in the UK for being child porn:
So why are Marchi, Rial, and Clark dubbing child porn?
Here's a trailer.
The power of two hearts connected. The "beautiful girl sexy battle action" anime is set on five artificial islands. Mamori is a "mermaid" transferred to one ...
www.youtube.com
And Funimation's version:
Pre-Order Valkyrie Drive: Mermaid on Blu-ray, DVD, & Digital HD combo pack: http://funi.to/2lNXZGz Synopsis: When Mamori Tokonome is sent to Mermaid Island, ...
www.youtube.com
Sadly Monica's character isn't featured in it. She's uh, this one:
https://valkyriedrive.fandom.com/wiki/Charlotte_Scherzen
Note, "She is the first Liberator to have inverted nipples!" Uh. Because that matters. Japan, I swear to god.