A decade ago, mankind witnessed the deadly potential of weapons caused by the Great War. To avoid another catastrophe, governments worldwide have resorted to espionage to fulfill their agendas. In the Din Republic, Lily is an enthusiastic young girl who aspires to become a spy and serve her nation. However, she begins to doubt her abilities, as she struggles to perform well academically. Lily's passion is reignited when she is offered provisional graduation by joining the spy team Lamplight, which she eagerly accepts despite the enigmatic nature of the opportunity. Upon arriving at her destination, Lily is surprised to find six other girls waiting there, all of whom have faced their own academic difficulties as well. A mysterious man named Klaus soon appears and reveals they must complete an "Impossible Mission": to infiltrate the Galgad Empire after just one month of training. Although skeptical, the girls eventually agree to work together under Klaus' guidance—as this might be their only chance to prove their worth as spies.

In the eyes of the public, Fudou Aikawa and Desumi Magahara are sworn enemies who have nothing in common. Fudou, also known as "Red Gelato," is the leader of the hero squadron "Gelato 5," whose mission is to bring about world peace. On the other hand, Desumi is the minion leader of "Gecko," a villainous organization seeking world domination. However, despite these differences, their relationship is not quite what it seems. When they are not making a show of being at each other's throats, Desumi and Fudou continue to pursue a forbidden love. Going on dates, baking sweets for one another, and meeting up as often as they can despite their hectic schedules, the two inexperienced lovebirds pave the way for their own unique relationship. Though their public lives are worlds apart, Fudou and Desumi will stop at nothing to make their seemingly impossible romance work.

After an eventful winter break, Kyoutarou Ichikawa and Anna Yamada reunite with a stronger bond. They continue to grow in their own ways, with Yamada taking on more challenging photoshoots and Ichikawa maturing both physically and emotionally as he tackles his affections for Yamada. However, spending time together outside of school allows for their relationship to deepen, and it becomes increasingly difficult to deny their budding romantic feelings. Grappling with these unexpected and new emotions, Ichikawa and Yamada realize that, with the passage of time, their relationship is bound to change—and they must ultimately decide whether they wish to remain close friends or finally become a couple.

"Kings" are individuals who have been bestowed with incredible supernatural powers and granted the ability to recruit others into their clans. Protecting the lives and honor of their clansmen is an integral part of the Kings' duties. After a video depicting the heinous murder of a Red Clansman spreads virally, the unassuming student Yashiro Isana is accused of homicide. Now, a manhunt is underway for his head, bringing him into contact with the infamous "Black Dog" Kurou Yatogami—a skilled swordsman and martial artist determined to follow the wishes of his late master, the Seventh King. Meanwhile, the current Red King, Mikoto Suou, faces his own imminent demise as the search for Yashiro narrows. But during Yashiro's struggle to prove his innocence, a greater conspiracy is unraveling behind the scenes; clouds begin to appear in his memory, and close friends start to question his very existence. What began as a simple murder is now leading towards a full blown war between Kings with the very fate of the world at stake. [Written by MAL Rewrite]