Terra of the Left, real name unknown, is a character introduced in Toaru Majutsu no Index. He belonged to the God's Right Seat, and was notable for his ruthless actions against non-Christians. He appears as one of the antagonists of the God's Right Seat Arc where he serves as the primary antagonist of the Document of Constantine Arc. He's the most cruel and psychotic of all the God's Right Seat and Roman Church members.
After the failure of Vento of the Front to eliminate Kamijou Touma after declaring him as an enemy of the Roman Catholic Church, Terra initiated an attack against Academy City through several civilian disturbances which was centered on the French city of Avignon.
Terra of the Left displayed an abhorrent and vile personality that equals only his actions. He was also one of the very people who knew about Touma's memory loss, although he failed to divulge his knowledge before his death.
Terra of the Left was featured in the trailer for the Toaru Majutsu no Index II series but nevery actually appeared physically in the anime. Instead, he made an appearance on the phone when Acqua fo the Back was with Vento and they were leaving Academy City.