According to String Theory, there are an infinite number of parallel universes, each one just a slightest bit different than the other. This is a oneshot about a history where Izayoi and Canaria never met. Izayoi is instead adopted into Tenkawa Household during the peak of his troubled childhood where he becomes brother to the young Maihime. No prior knowledge is required to read.

A story about a man named Shan Vile Merkava who was killed in 1945 during the war against the Neuroi and was experimented on by the Germans and was forced to use an ancient relic known as the Sword of Light. After he was killed, the relic had kept his mental state alive but his mortal body to be destroyed as he is now a spirit with an immortal body that seeks out to take revenge.