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.

After years of animosity, the leaders of Osaka's Somei and Tokyo's Miyama yakuza groups have called a truce—by arranging an engagement between their respective grandchildren, Yoshino Somei and Kirishima Miyama. To this end, 17-year-old Yoshino moves to Tokyo to live with the Miyama family and attend school with her new fiancé. Although Kirishima is all smiles and perfectly polite, there is something unsettling about his demeanor that Yoshino cannot put her finger on. Yoshino's suspicions are soon confirmed: despite his manners, Kirishima is a masochistic maniac. He hurts people without batting an eye and also revels in being punished verbally and physically himself. What he wants most is a spoiled and arrogant fiancée who will ruin his life. When Yoshino does not quite meet his expectations, he reveals his true colors and openly insults her. However, instead of running away in fear, Yoshino decides to take revenge by making Kirishima fall in love with her and then ruthlessly breaking his heart.

Haruka Nanase and Makoto Tachibana have started middle school and must adjust to the changes that come along with growing up. While Makoto fits in with his classmates and remains positive about swimming, Haruka struggles to befriend others or join his school's swim club, as his previous issues with swimming trouble him. Distancing himself from his lively classmates and the swimming club, he has difficulty deciding which club to join instead. The rest of his classmates, including Makoto, are also hesitant as to which clubs to participate in. After an argument leads them to join the swimming club anyway, the boys strive to hone their skills, harmonize their swimming styles, and refine their conflicting feelings toward swimming and each other. As determination and talent run high, Haruka and Makoto—along with their classmates—discover themselves and improve their talents during their starting days.

Second season of Hyakka Ryoran: Samurai Girls.