Mutant Girls Squad is the story of Rin (Yumi Sugimoto), a girl born a mutant, who ends up an orphan and being hunted by those that want to exterminate her kind from the face of the Earth. Luckily she meets some fellow mutants. Unluckily, those mutants hold some pretty out there values and opinions. Expect a lot of fake blood to be spilled.
The directors of this film have worked on such films as The Machine Girl, Azumi and RoboGeisha, and it shows. This is a gore fest of a film, filled to the brim with flying body parts, high pressure blood and needlessly graphic body horror imagery. All in good fun, of course, and if you're a fan of the genre, you're going to love the exploitation on show here.
I also had no real problems with the story. The three main girls had distinct personalities, the setting was suitably bat guano insane, and the action was fun to witness. The main bad guy was pretty cringy, but in a way that oddly fit the whole aesthetic of the film.
That being said, this is probably the most perverse Japanese gore film I've seen, and I've seen some good ones. There are films that might have had more private parts on display, but even they were more... I want to say tasteful, but that doesn't really apply with any of these films. Less... childishly blatant, perhaps?
Still, if you've liked, for example The Machine Girl or Tokyo Gore Police or Ichi the Killer, this is definitely worth checking out. It's not quite as good as those three, but it's still a high octane experience unlike anything seen in Western media.