In the near future, humanity has taken its first steps towards journeying into the far reaches of the galaxy. Upon doing so they discover a huge race of insectoid aliens known as Space Monsters. These aliens seem dedicated to the eradication of mankind as they near closer and closer to discovering Earth. In response, humanity develops giant fighting robots piloted by hand-picked youth from around the world. Shortly after the discovery of the aliens, Noriko Takaya, the daughter of a famous deceased space captain, enters a training school despite her questionable talents as a pilot. There, she meets her polar opposite, the beautiful and talented Kazumi Amano, and is unexpectedly made to work together with her as they attempt to overcome the trauma of war as well as their own emotions.

Katakura Kippei is in every way a high school playboy. Spending his days flirting with any girl he can see, responsibility is the last thing on his mind. Life takes an unexpected turn for him as one day he returns home to find himself with the full-time task of caring for his 5-year-old cousin. Kippei's aunt Miyako had disappeared, appearing to have abandoned his cousin, Yuzuyu. With Kippei's lack of responsibility and knowledge of childcare and Yuzuyu's injured heart with the disappearance of her mother, their time together is in for a bumpy ride.

With her gorgeous, tan skin and long, bleached hair, former high school swim team member Momo Adachi seems like the kind of girl who could get any guy she wants. In reality, however, she is only in love with Kazuya Toji Toujigamori, a baseball player whom she fell for in junior high and who reportedly only likes pale-skinned girls. Despite her attempts to change her appearance, many of her jealous classmates have begun spreading rumors about her promiscuous and easy to get with personality. Momo's friend Sae Kashiwagi is always there to comfort her, but is secretly the source of the rumors about Momo as part of her own scheme to steal Toji. Further complicating things is Kairi Okayasu, a popular male student at Momo's high school who has publicly declared his love for her and is determined to date her. Hoping to find love in a nearly impossible predicament, Momo must navigate complicated love triangles, back-stabbing friends, and her insecurities about her appearance to discover who she really is.

Gorou Honda, a little boy obsessed with baseball, has always admired his father, Shigeharu. Wishing to follow in his father's footsteps, Gorou dreams of becoming a professional baseball player. In turn, his son's starry-eyed admiration encourages Shigeharu to keep persevering, despite his late wife's death and his unsatisfying position on the second-string team Blue Ocean. Unfortunately, an elbow injury forces Shigeharu off the team, and he falls into despair. However, after an offhand joke from his childhood friend, Shigeharu reevaluates his choices and decides to keep playing, leaving behind his prime position as pitcher and taking up the bat. Now motivated more than ever, Gorou works hard to carve his way in the Japanese Little League.