Despite not understanding much about fleeting teen romance, first-year high school student Kazuhiko Nukumizu still wonders how he would react if his life were to be turned into a love story. Regardless, as a self-proclaimed background character, Nukumizu is satisfied continuing his life as an introvert with a negligible social life. However, he suddenly finds himself too close to the spotlight when he witnesses his popular classmate Anna Yanami be rejected by her childhood friend in the middle of a family restaurant. While Nukumizu wishes he could just forget what he saw and move on, Anna ends up forcefully confiding herself in Nukumizu, lamenting her status as a childhood friend fated to have her beloved stolen. As he becomes dragged into Anna's situation, Nukumizu soon gets caught up in the relationship drama of two more girls: Lemon Yakishio, an outgoing member of the track and field club; and Chika Komari, a shy member of the literature club. Now thrust out of his comfort zone, Nukumizu finds himself a major character in the lives of too many losing heroines.

Tokiyuki Houjou, a carefree eight-year-old noble, is content with the serene life in Kamakura and shows little regard for the serious responsibilities that come with his eventually succeeding his father as the next shogun. Instead of dedicating himself to rigorous training in swordsmanship or archery, Tokiyuki excels in the art of evasion, skillfully dodging his advisors and discovering perfect hiding spots. However, his peaceful existence is shattered when a sudden coup brutally wipes out his clan. Overwhelmed with guilt for being the sole survivor, Tokiyuki contemplates joining his family in death. However, his fate takes an abrupt turn when the enigmatic priest Yorishige Suwa suddenly shoves him onto a battlefield. Yorishige, who prophesies that Tokiyuki will one day become a great hero, leaves the boy with no choice but to navigate his way free of enemy soldiers. As Tokiyuki struggles to survive against these foes, he finds a new thrill in raising the stakes of his usual hide-and-seek games. With a renewed sense of purpose and the promise of powerful allies from Yorishige, Tokiyuki vows to avenge his family—not through his capability to fight, but through his extraordinary talent for running away.

In a war against four overpowered races—angels, demons, undeads, and humanoid beasts—humanity could only prevail thanks to its champion Sid, who defeated the other races' champions and sealed away their armies in four pyramids. In an age where Sid's existence has become but a legend of the past, Kai Sakura Vento is one of the many conscripts tasked with monitoring the pyramids in fear that these old foes would escape. On a peaceful day while spending time with his friend Jeanne E. Anise, the world is suddenly overwritten, transporting Kai to an alternate reality where humanity has nearly been annihilated by the demons and forced into hiding. To make matters worse, his very existence has been erased from this world; all of his friends, including Jeanne, who leads the local resistance efforts in this world, have forgotten about him. Trying to investigate the remains of his former world, Kai encounters Rinne, an enigmatic young woman trapped in a pyramid. Mysteriously inheriting Sid's legendary sword Codeholder, Kai manages to free Rinne from her imprisonment. Determined to fix this reality, Kai joins forces with Rinne and Jeanne to free humanity from demonic rule. But if the valiant soldier wants to have a chance at returning to his original world, he will first have to uncover the cause behind the mysterious alteration of reality.

Jun Shirasaki and the Jinguuji sisters are childhood friends and neighbors. When Jun's first girlfriend, the older sister Rumi, breaks up with him, she says something that complicates the three people's relationship, their first loves, and their romance—? (Source: MAL News)