As the Holy Empire rises to power, the neighboring lands begin to gradually fall under its control. The Empire's conquest eventually reaches the small island of Erin, home to the Gael tribe. There, a priestess named Riannon is kidnapped to be offered as a living sacrifice to the demon king Arawn, a malevolent being rumored to have caused untold destruction in the past. Riannon's brother, First Warrior Arthur, rescues her, when Arawn suddenly materializes before them as a handsome grey-haired man. Hiding his true identity and remaining enigmatic, Arawn pledges his power and leadership to the tribe's cause and joins Arthur, Riannon, and their merry band of friends—including a talented swordsman, an agile hunter, and a group of ecstatic pixies—as they fight back against the Empire, while uncovering the dark secrets of the land along the way.

With his mother taken away from him and having lost everything, Lag Seeing is now a letter whose delivery has been assigned to Gauche Suede, a Letter Bee. Despite their troubling start, the two of them become friends, leading Lag to realize what his aim in life is: to deliver people's most important feelings in the form of letters, just as Gauche has done.

Third season of Teekyuu series.

Due to rising sea levels and a rapidly declining human population, androids have been engineered to perform most menial tasks, allowing humans to focus on other things. Aside from providing manual labor and customer service, androids also entertain humans through Babel—a tower where participants captivate audiences with song and dance to clear Climb Stages. The higher the climb, the more prize money is awarded. Androids Cobalt, Chrom, Neon, and Kei are down on their luck and about to have their electricity cut off from unpaid bills. Desperate to make a quick buck, the group decide to become Babel climbers. However, winning the audience's favor is a great challenge. Dejected but unwilling to give up, Cobalt resolves to somehow improve their chances after watching an impressive performance by STAND-ALONE—the top climber unit. When the group stumbles across a mysterious choreographer willing to give away his routine, Cobalt sees this as their only way up. With the help of their human companion, Esora Shibaura, the androids form the unit KNoCC to tackle the daunting climb to the top of Babel, but they must also overcome android-based discrimination along the way.