During his school computer class, Saneatsu Narita is presented with a strange screen posing a yes-or-no question that quickly disappears. The next day, Saneatsu wakes up to a world where everyone, save for himself and a few others, is dead. An announcement from a mysterious figure known only as the Emperor begins to shed light on the situation. The question that Saneatsu saw on the screen is part of a game called Tasuuketsu. Every day, the survivors will see a question appear on a screen, and answering it will determine who lives to see the next day. Responding the same as the majority will guarantee death, and the last player standing will earn the right to meet the Emperor. Saneatsu resolves to beat the Emperor at their own game, making use of the hidden envelopes containing powers that can aid the players. With the help of his small group of friends, Saneatsu must avoid falling into the machinations of the other players and win this wicked game.

After Rio escapes the capital of the Beltrum Kingdom with his former teacher Celia Claire and his bond spirit, Aishia, he finds himself in a dire situation once again. As it turns out, multiple people from his past life in Japan are suddenly scattered around the new world. Rio rushes to their help, saving a small group and taking them under his wing. To his surprise, one of the rescuees is his old self's childhood friend Miharu Ayase. The newcomers were not the only ones summoned. With old friends and new allies by his side, Rio sets out to locate the other abductees while searching for a way to send them back to Japan. However, Rio never loses sight of his main goal: avenging his mother's death.

On the dusty streets of the castle town Dayah in the Fortna Kingdom, a young orphan named Nina steals for survival. Experiencing one tragedy after another, she has little to hope for in her life. Believing it best for Nina, her closest friend, Saji, hands her over to Second Prince Azure Seth Fortna, who has been searching for someone with unique and intense deep-blue eyes—just like Nina's. The kingdom's princess, the revered Astral Priestess Alisha, has recently died on her way to the Galgada Kingdom, where she was to marry the tyrant First Prince Sett. However, her death is concealed for political reasons, and that is where Nina needs to step in. With nowhere else to go and no one to turn to, Nina assumes Alisha's identity and future duties. But with each moment spent with Azure, Nina feels herself drawn to his warmth, fearing that once she is wed to another, nobody will remain to remember her true self.

As the Love Live! Competition draws to a close, Kanon Shibuya takes an offer to study abroad and bids farewell to her friends and fellow members of the school idol group Liella!. Although they will live on opposite sides of the world, both Kanon and the group remain motivated to continue their idol activities. Unbeknownst to Kanon, however, her plans are cut short by Wien Margarete's parents, who request that Kanon remain in Japan for another year so that their daughter can learn from her. While Kanon finds herself in awkward limbo, Wien cannot bring herself to join her once fierce rival Liella! and decides to start a group of her own. Not wanting Wien's determination to go to waste, Kanon joins the new group, recruiting her former group member's sister Tomari Onitsuka in the process. As the newfound unit strives to wash off Wien's controversial past, the new Liella! is also wrestling with the struggles of losing their irreplaceable center.