After succumbing to an unenviable fate, Kiritsugu Emiya has left Shirou Emiya the duty to save mankind in his place. The world is dying and time is ticking, but when the salvation Shirou seeks is at the cost of his only family left—his younger sister—will he still have the heart to pursue this duty? Shirou is now pressed with the choice to continue being a hero of justice—or become the very evil his ideal has vowed to vanquish. The orphan is alone once again, yet his body is still made of swords. The Fifth Holy Grail War now begins with his oath under snow. [Written by MAL Rewrite]

After an embarrassing high school class reunion with their successful classmates, who have "proper" jobs, relationships, and even children, the Matsuno sextuplets return home to sulk about their status as NEETs. They spend the night drinking away their sorrows, eventually falling unconscious, until they awaken in a strange world of memories, centered around one of the brothers' biggest high school regret.

As the sextuplets navigate this memory world, they encounter their embarrassing past selves from high school, as well as those of their friends. All the while, they try to uncover whose regret was great enough to trap them in this strange world, so that they can make their way back to reality. However, they're running out of time; this world of memories is unstable, and the sextuplets may lose their chance to make things right if they're too slow....

1532. Esteban, age 12 is a foundling from Barcelona, with a mysterious power of ordering the Sun to appear, for which he is called "Child of the Sun." Upon the death of his adoptive father, Esteban learns he was rescued as a baby from a sinking ship in the ocean. The mysterious medallion that Esteban wears since ever has a trace somewhere in the New World, probably coming from the Mysterious Cities of Gold. Esteban leaves Spain to find his parents and find out who he is. On the way he meets Zia, an Inca girl who was kidnapped from her people years back and has exactly the same medallion as him. Later on, they are joined by Tao, a young Galapagos robinson, the last descendant of the Empire of Heva, an Empire said to have built the Cities of Gold. Following Coyolite, the shining star represented on their medallions, the three children travel through the unexplored New World, searching for the Cities of Gold, believing that this way is leading them to their lost parents.

Included with the third and fourth volumes of the Asobi Asobase Blu-ray and DVD releases.