Akikan! was originally a series of Light Novels written by Riku Ranjo and illustrated by Hiro Suzuhira that started serializing in 2007. They were later adapted into a manga and a Twelve Episode Anime by Brains Base. Compare with Inukami!.Kakeru Daichi, sixteen years old. Collector of rare cans. Considering the first two things, no wonder he's never had a girlfriend. That is, until he finds a can of melon soda he purchased transforms into a girl. She is an Akikan, one of the few that have begun to appear recently. A strange take on the Magical Girlfriend genre, but with all the same craziness. The rest of the cast is quirky, including the government officials researching the case and Kakeru's classmates.
Akikan! provides examples of the following tropes:
Clingy Jealous Girl: Melon, who got upset that Kakeru would "drink" another brand of juice. She also beats him up at the end of episode 12 when he tries to take on another Akikan.
Najimi in episode 5 and at the end of episode 12.
Both Yell and Melon don't seem too happy when Najimi and Kakeru seem to be getting close to each other during their date at the water park in episode 8. Yell even tries to disrupt/break down the ferris wheel before Melon stops her.
Yurika towards Najimi anytime she thinks Kakeru makes her cry, or is getting too friendly with her.
Combined Energy Attack: Melon, Yell and Budoko combine their powers to take down the strongest Akikan in one shot.
Conservation of Ninjutsu: In the final battle, the three main Akikan take out dozens of fake Akikan with little trouble.
Covert Pervert: Najimi's mind goes to some dirty places when Kakeru is involved. With the smiling and the laughter and the blushing...
Day In The Life: Episode ten, which focuses on the three Akikan girls at home alone with the human cast either being reduced to cameos or not appearing at all.
Declaration of Protection: When Najimi tells Melon about her backstory with Kakeru where 2 years before the show started, he saved her from some thugs by wrestling the gun away from them, and then shooting and wounding them. It caused a lot of controversy in the city he lived in however, so he was forced to move to a new place.
Mood Whiplash: Episode 5 starts out pretty innocent enough, then after Kakeru cancels his date with Najimi, she accidentally catches a glimpse of them going to a baseball game. In the heat of the moment, orders Yell to punish him. Yell responds by giving Kakeru a pretty deep cut to his stomach, which bleeds pretty severely.
Yandere: Najimi falls into this trope briefly, ordering Yell to "punish" Kakeru after accidentally seeing them attending a baseball game together in episode 5. Yell manages to strike a pretty deep cut into Kakeru before being stopped.