Practice Makes Squid Perfect?! Ink That A Festival?!
Squid Girl asks the Lemon to help her invasion club practise for proper invasions, though really she wants to test her ability to invade without Chizuru around. After Squid Girl gets into a fight with Eiko, they decide to stop talking to each other. As everyone attends a summer festival, Squid Girl ends up getting separated from her friends. As a shower hits, Eiko decides to search for her and meets Kozue, who helps her find and make up with Squid Girl.
Aired 25/12/2011EP 12 - Practice Makes Squid Perfect?! Ink That A Festival?!

Squid Girl 2
The nefarious Squid Girl is back to continue her self-appointed mission to invade the surface world. Or that's what she would do, if she could just stop getting distracted by squidding movies, reading squidly manga, and making friends as only a squid could make them. Squid Girl must overcome not only danger found at every turn, but her own squidly good nature as well.
(Source: Anime News Network)