Stride—an extreme sport that combines parkour, free running, relay, and sprinting—is what made first year high school student Nana Sakurai enroll in Honan Academy, after being captivated by the school's stride team. Sharing the mutual intention of joining the team is fellow first year and stride maniac, Takeru Fujiwara, and together they request to join. Much to their dismay, however, the stride club is no longer active due to lack of members, and they are now operating under the shogi club. In order to revive the stride club, Nana and Takeru recruit first year Riku Yagami—a fast runner who is interested in almost every sport. With this new team, the club now aims high at a new goal: to win the prestigious End of Summer competition, and bring the Honan stride team back to their prime.

In the early 20th century, the discovery of the substance Cavorite allowed the production of advanced military technology and steered the country toward conflict. London is now divided by a wall, and the Kingdom and the Commonwealth of Albion battle a silent war where espionage is the only weapon that can destabilize the enemy. A group of girls from the prestigious Queen's Mayfaire school work as undercover spies for the Commonwealth. Led by Dorothy, an experienced driver with a striking personality, their group includes the talents of Ange le Carré, a cold-blooded liar and expert sharpshooter; Chise, a proficient samurai; and Beatrice, a voice-mimicking specialist. They use their unique individual skills for the Commonwealth to survive in a dark world filled with conspiracy, mystery, and infiltration. In the shadow of the war, they have only one goal in mind: completing their mission.

In the continent of Astraea, a man falls from the sky, possessing no memories other than his name, Yuuki. An elf named Kokkoro finds him, introducing herself as his guide in the world they are about to traverse. With Kokkoro's guidance, Yuuki is able to learn how this world works, from battling monsters to handling currency. To earn money for their journey, Yuuki and Kokkoro decide to go to a nearby guild association to accept a simple quest. In their expedition, they meet Pecorine, a somewhat gluttonous but charming girl skilled in battle. The next day, they also meet Karyl, a cat girl specializing in magic. After some time, a bond of friendship and camaraderie forms between them, and the four decide to create a guild of their own. As they continue their adventures, they explore the world, meet new people, and will perhaps uncover the mysteries behind Yuuki's missing memories.

Following an automobile accident that claims the life of his parents, Teppei Arima is taken in by his grandfather and introduced to the world of the rich and the elite. Compared to his humble upbringing, Isshin Arima's lavish lifestyle surprises and stuns the young teenager. In return for the gracious hospitality, Teppei is expected to continue the family business by replacing his grandfather as the head of Arima Financial Combine, and to prepare him for these responsibilities, he is enrolled into an esteemed high school. Along with his recently acquired celebrity status and affluence, Teppei is informed of an arranged marriage with the equally prosperous Sylvia van Hossen, thus, beginning the thrilling escapades of his new life!