TRINITY SEVEN Episode 10: Game Master and Satan Slave
Episode 10 of 12 of TRINITY SEVEN, aired December 10, 2014, 25 minutes. Available with English subtitles and dub where released.
Episode summary
The ultimate demon lord, Astral Trinity, shows up in the form of Arata with a grotesque new appearance. Hijiri appears as well, and the others discover that she is a high-level mage whose goal is to kill Arata and destroy the school.