Lev Lainur Flauros

Professor Lev Lainur Flauros, born Lev Lainur and localized as Leff Lynor Flauros, is the a major antagonist in Fate/Grand Order. He is the secondary antagonist in Observer on Timeless Temple, a posthumous antagonist in Cosmos in the Lostbelt, and the key character in Clock Tower 2015, a prequel tie-in novel.

His true identity is revealed to be the host of Flauros, one of the seventy-two Demon Pillars of King Solomon, being responsible for the deaths of Olga Marie Animusphere and several Chaledea Masters, including seven A-Team who would later revived by Alien God and became the Crypters.

He is voiced by Tomokazu Sugita (who also voiced Goetia and all of the 72 Demon Pillars) in the Japanese version of all his animated appearances. In the English version of Fate/Grand Order -First Order- anime, he is voiced by Jalen K. Cassell.

Fate/Grand Order (2016)
In Fate/Grand Order, because of the suicide never happened in this timeline, Lev Lainur accepted Goetia's offer to abandon his humanity and become one of the seventy-two Demon Pillars. He was described as an "approachable young man", he has dedicated his life to protecting humanity. However, this was all a guise, a deception to fool his allies in Chaldea.

Lev's true nature is revealed to be that of a very malicious sadist and nihlist to the core. He has decided that humanity has no future, and his goal is the incineration of human history after 2016.

Clock Tower 2015
In Clock Tower 2015, it is revealed that Lev possesses three personalities, Lev Uvall, Lainur Gusion and Mr. Flauros, the current personality displayed in Clock Tower 2015. They represent the past, future and present of Professor Lev as a whole. He is also a good friend to Touko Aozaki.

Lev Uvall (Past)
Lev Uvall is a man who values the "past". In his younger persona, Lev was a pure academic magus. All his efforts were poured solely into his theory and magecraft. He cared naught of any other responsibilities, the application of his magecraft, his lineage, or building his faction.

From Lev's perspective, those magi were the same as the plebians that were "normal people". Due to this, Lev was often mocked as "research fanatic" or "the indoor chairman". His relationship with Touko Aozaki is Platonic, since Lev Uvall had no experience to comprehend luxuries such as love.

Lainur Gusion (Future)
Lainur Guision is a passionate Magus who goes extremes over the prosperity of the magic, even at the cost of sacrificing his past and present selves. His relationship with Touko Aozaki is purely perverted, seeing her as a possession rather than a friend or a love interest.

Mr. Flauros (Present - 2015)
The Clock Tower 2015 version of Mr. Flauros is the more neutral existence in Lev's life and personalities, trying to balance between the ignorance of future from his past persona, and the denial of past from his future persona, to the point of killing himself from preventing Goetia from manipulating his future into one with the Evils of Humanity.

In the original timeline of Clock Tower 2015, Lev is a decent man who never turns his back on humanity in the first place, but Goetia destined him to become the seventy-second Demon Pillar, steadily overwriting his personality with that of the Demon God Flauros. Lev recognized what was happening to himself and managed to commit suicide in time, refusing to become a puppet of Goetia.

Unfortunately, the Fate/Grand Order version of Lev failed to do this, and thus successfully becoming a host to one of the Demon Pillars.