The all-powerful invertebrate invader from the deep, Squid Girl, faces off against Nagisa, the one living thing on earth (including plants and microbes), who is actually afraid of her. Can Squid Girl manage to lose against the only person she has an advantage over?

Nagisa’s polar opposite is Sanae, a girl with an unhealthy obsession with Squid Girl. Is she willing to overcome the odds to get Squid Girl to fall in love with her, or does she actually enjoy her daily beatings from a swarm of tentacles?