Yuu Izumi leads a high school life filled with one mishap after another. No matter how improbable the situation, unfortunate events strike him at every turn. In possession of such terrible luck, Izumi enters his second year with a single wish in mind—to spend more time with his affectionate girlfriend, Micchon Shikimori. Cute, athletic, and caring, Shikimori is immensely popular at their school. But since they began dating a year ago, Izumi has witnessed a surprising side to his otherwise adorable girlfriend: when the need arises, she turns incredibly cool! His misfortunes are easily avoided when she is there to protect him with an awe-inspiring look on her face. Charming in every way, she never ceases to make his heart skip a beat. Unfortunate as he may be, Izumi is sure to see his days of bad luck end thanks to the cute yet cool Shikimori.

In 1863, Izuminokami Kanesada and his partner, Horikawa Kunihiro, arrive in the streets of Edo from the future to investigate their master's reports of an upcoming enemy invasion. As humanoid manifestations of the famous Toshizou Hijikata's swords, they have been tasked with protecting history from the Retrograde Army that seeks to alter it. Soon enlisting the help of other sword warriors, they continuously battle the mysterious army throughout the Bakumatsu period. However, their journey will not be an easy one. Fraught with blood and betrayal in the chaotic era closest to their hearts, the duo will be forced to make difficult decisions with everything they care about on the line.

The story begins in a small town, Pennsylvania in 1838. Jeanie MacDowell is a cheerful and beautiful girl with light brown hair. Jeanie enjoys playing the piano and loves taking piano lessons from her mother. Steven, a good harmonica player, and Bill, a black boy who is very good at playing the banjo, are great friends of Jeanie's. They enjoy playing music together like a small band. However, Jeanie's happy life changes dramatically after her mother suddenly passes away. Experiencing many difficulties and learning the importance of life, she decides to devote her life to helping many people suffering from illness. This series is a highly emotional love story about the relationship between young Stephen Foster, who later becomes a famous composer and author of children's songs, and young Jeanie MacDowell, who becomes Stephen Foster's wife.

Two years ago, a mysterious wind swept over the Earth without warning, taking everyone's memories with it. Not knowing their names or even how to speak, cars crashed, planes dropped from the sky, and society crumbled in an instant. One young man happens to wander into a military testing facility, where he meets Johnny, a young boy who underwent experimental memory enhancement treatment and could, therefore, still remember who he was. Johnny names the young man Wataru and teaches him everything that he can before his frail body fails him. Wataru sets out on a journey to see if he can find other people like him, and in San Francisco, he meets a mysterious silver-haired woman named Sophia, who refuses to speak about her past. Sophia says that she is heading to New York, and decides to travel together with Wataru. As the pair make their way across America, they learn about what has happened to the rest of society, and what the essence of humanity really is.