On the surface, the thought of Kyouko Hori and Izumi Miyamura getting along would be the last thing in people's minds. After all, Hori has a perfect combination of beauty and brains, while Miyamura appears meek and distant to his fellow classmates. However, a fateful meeting between the two lays both of their hidden selves bare. Even though she is popular at school, Hori has little time to socialize with her friends due to housework. On the other hand, Miyamura lives under the noses of his peers, his body bearing secret tattoos and piercings that make him look like a gentle delinquent. Having opposite personalities yet sharing odd similarities, the two quickly become friends and often spend time together in Hori's home. As they both emerge from their shells, they share with each other a side of themselves concealed from the outside world.

As the graduation ceremony at Katagiri High School comes to an end, Kyouko Hori, her boyfriend Izumi Miyamura, and their friends begin to look back on their time as students. The moments they shared together may be fleeting, but each one is a colorful piece of their precious memories.

College student Yuuhi Amamiya's monotonous life is turned upside down with the appearance of Sir Noi Crezant, a talking lizard claiming to be a knight of justice. Crezant elaborates that the world is in peril—threatened by the mage Animus who wishes to annihilate it with his Biscuit Hammer, an enormous structure suspended in Earth's orbit. As the newly appointed Lizard Knight, Yuuhi must fight alongside other Beast Knights to protect the princess and save the planet from destruction. Unimpressed by the prospect of risking his life, Yuuhi continues his day as usual—until a golem created by Animus suddenly confronts him. Yuuhi is instantly overpowered, but his neighbor, Princess Samidare Asahina, luckily rescues him. To his surprise, Samidare's intention starkly differs from Crezant's; instead of saving the world, she aims to destroy it with her own hands. Captivated by her firm ambition, Yuuhi resolves to become stronger and help Samidare realize her goal. As the pair continues to fight against Animus' golems, Yuuhi finds himself gradually gaining an interest in life—but the chains of his past trauma may restrain him from progressing further.