Remu Mikage had a video call with his sister, Shiki, who was studying at the technologically advanced Okinotori-island Mega Float City. During their conversation, Remu learned that Shiki's audio and visuals were completely artificial, and that she had used neural-linked nanomachines to upload her consciousness onto a computer. Shiki stored her physical body in a "body pool" in order to improve her academic performance. Initially supportive of his sister, Remu's opinion changed with the "Early Rapture" disaster. The "Early Rapture" calamity induced a coma or death to all who had uploaded their consciousness. Remu was heartbroken when he discovered Shiki's vacant living quarters. However, Shiki materialized at the door with no recollection of her family or personal history. A violent group of researchers were also in pursuit of her, forcing Shiki and Remu to flee while taking advantage of Shiki's newfound nanomachine manipulation abilities.