Naota is a detached sixth-grader afflicted by the pangs of puberty. When a crazed girl on a motor scooter runs him over and brains him with a bass guitar his life gets weird - giant-fighting-robots-shooting-from-his-skull weird.

Naota’s attacker, Haruko, is now his dad’s live-in housemaid and she says she’s an alien. Mamimi names the robot from Naota’s head Canti, the God of Flame. Does Canti have anything to do with the mysterious fires burning all over town?

The president of Naota’s class, Ninamori, is no stranger to the dirty deeds of politics. She rigs the vote to cast him as the lead role of their class play. But she gets in over her head after a crashing introduction to Haruko.

There’s a guy claiming to know Haruko and why she’s using Naota’s head as a portal for oversized battling robots. It’s too late, though, as a malfunctioning satellite is heading straight for them and it’s up to Naota to stop it!

Jealousy spurs an epic pellet gun battle between Naota and his dad over Haruko. The object of her desire will be revealed, and she’ll do whatever it takes to get him!

A hand statue looms over the Medical Mechanica building, threatening to iron out the city. As Mamimi’s new pet turns out to be a crucial element to Haruko’s plans, Naota finally proves that he’s no pushover.

Kana Koumoto - a cheerful 17 year old who can often be a klutz and nosey. One day, while hanging out with her besties (Pets, Mossan and Hijiri), Mossan starts making a rocket using empty soda bottles.

One morning, Kana and her besties witness Hijiri kissing a college student Toshio inside his car. Acting more mature than any of her classmates, Hijiri suggests Kana and her besties to do a photo shoot with Toshio.

Mossan is the most mature of all 4. With a passion of becoming a designer, she has been working outside of school. Upon discovering her working towards a fashion contest, Kana feels the urge to help her, which rubs her the wrong way.

The 4 girls come watch the basketball game that their Sasaki is a member of. Kana has been secretly in love with Sasaki, whom Haruko ends up making out with. This triggers Kana's NO to activate, but she notices that and runs away.

One hot summer day, the 4 girls and Haruko are playing in the pool. They notice that Pets is missing. Kana later hears from her classmate Aida that Pet's family is very rich and they are moving to Mars.

Depressed, Kana flips over the collection of photos she took with her besties. The next day, the 3 girls gather by the beach as they watch the rocket Pets is supposed to be on.