- Adaptation Displacement: These books are virtually unknown outside of Japan, and even then, they're pretty niche. Compare that to Shin Megami Tensei, the franchise (initially) based off said books.
- Complete Monster: Loki is the Big Bad of the first book and the catalyst for the trilogy as a whole. A demon summoned by Akemi Nakajima to get revenge on two students, Loki orders Nakajima to procure female sacrifices as compensation, including Nakajima's teacher Ohara, whom he impregnates. Initially following the terms of the deal, Loki has a teacher murdered against Nakajima's wishes. Lusting after Yumiko Shirasagi, Loki demands her as a sacrifice and betrays Nakajima when he refuses. He then manipulates the brainwashed Ohara into summoning him into the real world, and goes on a killing spree by devouring countless students and other innocent civilians. He attempts to rape Yumiko, and was only thwarted by the goddess Izanami's intervention, but nonetheless manages to fatally wound Yumiko in the process. In pursuit of the protagonists, Loki murders the loyal Cerberus and Yomotsu-Shikome, and tries to rape Izanami as well. A demon solely driven by his wanton lust for rape and blood, Loki sets the standards for future Shin Megami Tensei villains..
- Evil Is Sexy: Loki's descriptions liken him to a bronze Greek statue.
- Nightmare Fuel: The lovingly detailed descriptions of what Loki does to people. And how he eats.
- What an Idiot!:
- Nakajima. He summoned a deity-class demon with his program, sure, but he also neglected to include little details like the duration of the summoning, compensation, and conditions...
- Ohara has this as well. When Loki is defeated, she freaks out, and fiddles with the Demon Summoning Program, something she doesn't understand and can barely operate. She ends up summoning Set.
YMMV / Digital Devil Story