Chiaki believes in a world where the powerful control all, moving progress forward while the weak creatures who stagnate the world are removed.

• Don't complete the Labyrinth of Amala before the Tower of Kagutsuchi.
  
• Don't flag the Musubi or Shijima endings. (basically, don't trip both flags listed in either the Shijima or Musubi endings because you might get that ending instead).
  
• Yosuga Flag 1: Scene with Chiaki at Mantra HQ after Ose at Assembly of Nihilo
  You know what I’m saying, don’t you? -> Answer "Yeah, I get it."
  
• Yosuga Flag 2: Scene with Chiaki and Futomimi at Mifunashiro after Temple of Amala.
  I know you understand what I mean. -> Answer "I see your point." You will fight Futomimi instead of the Angels. This option is only available if you answered Yosuga Flag 1 properly.

Hikawa is a calm but dangerous man, as well as a heretic of the Cult of Gaea who actually initiates the Conception at the beginning of the game. His Reason of Shijima envisions a world where the passion of mankind is stripped in a sterilized world of silence.

• Don't complete the Labyrinth of Amala before the Tower of Kagutsuchi.
  
• Don't flag the Musubi or Yosuga endings. (basically, don't trip both flags listed in either the Musubi or Yosuga endings because you might get that ending instead)
  
• Shijima Flag 1: Speaking with Hikawa in front of Mantra HQ, after Obelisk (and shortly after the Musubi Flag 1 listed above).
  Do you not agree that the world should be ruled by serenity? -> Answer "Actually, I do."
  
• Shijima Flag 2: Speaking with Hikawa at end of Diet Building.
  Now, I’d appreciate it if you’d stand aside and cease with the interruptions. -> Answer "Fine by me." I believe this option is always given, but you cannot get the Shijima ending unless you trigger both Shijima Flags.

Isamu Nitta values individuality over all else, a world where nobody can be controlled by outside influences or forces.

• Don't complete the Labyrinth of Amala before the Tower of Kagutsuchi.
  
• Don't flag the Shijima or Yosuga endings. (basically, don't trip both flags listed in either the Shijima or Yosuga endings because you might get that ending instead)
  
• Musubi Flag 1: Talking to Isamu in Amala Network, after completing the Obelisk.
  Wouldn’t it be nice to have a world to yourself? -> Answer "I can relate."
  
• Musubi Flag 2: Scene with Isamu and Hijiri at the end of the Temple of Amala.
  Will you do it, for the sake of Musubi? -> Answer "All right." which will have the Demi-fiend dump Hijiri. This option is only available if you answered Musubi Flag 1 properly.

This ending is tied to the Demi-fiend's teacher, Yuko Takao, and is often referred to as the Freedom Ending, or sometimes the Teacher Ending. Although it is not technically a Reason, it works similarly to the three Reason endings.

• Don't complete the Labyrinth of Amala before the Tower of Kagutsuchi.
  
• Don't flag the Yosuga, Musubi, or Shijima endings.
  
• Freedom Flag 1: Scene with Aradia/Yuko at the end of Yoyogi Park, after getting the Yahiro no Himorogi. You have to pick two options here.
  Do you fear the suffering and humiliation? -> Answer "I can take it."
  Do you fear the deceit, the torment? -> Answer "I can take it." again.
  
• Freedom Flag 2: Speaking with Hikawa at end of Diet Building.
  Now, I’d appreciate it if you’d stand aside and cease with the interruptions. -> Answer "Can’t do that." Note that the scenes after this event appear the same, but if you rejected all three Reasons and fail to finish the Labyrinth of Amala, you'll get the Freedom Ending.
  
• Note: To be safe, tell Mitra at Diet Building you are not a demon. I don't believe this affects the ending, but can't be too careful.

This is the ending that you will achieve if you reject all three Reasons, fail to support Yuko, and fail to complete the Labyrinth of Amala. It is often referred to as the Neutral Ending, or sometimes the Demon Ending (though not to be confused with the True Demon Ending).

• Don't flag the Yosuga, Musubi, or Shijima endings.
  
• Don't complete the Labyrinth of Amala before the Tower of Kagutsuchi.
  
• Neutral Flag 1: Scene with Aradia/Yuko at the end of Yoyogi Park, after getting the Yahiro no Himorogi. You have to pick two options here.
  Do you fear the suffering and humiliation? -> Answer "...I’m terrified."
  Do you fear the deceit, the torment? -> Answer "...I’m terrified." again.
  
• Note: To be safe, tell Mitra at Diet Building you are a demon. I don't believe this affects the ending, but can't be too careful.

The True Demon Ending (TDE) is, in a way, both the most involved ending to achieve in Nocturne, but it's also one of the easiest to explain how to obtain it. This ending was added in the Maniax PS2 re-release of Shin Megami Tensei: Nocturne, which was the version localized for the West in 2004. This version also added the Labyrinth of Amala and the Fiends. So, perhaps it's no surprise that this ending involves this additional labyrinth.

As long as you complete the Labyrinth of Amala before entering the Tower of Kagutsuchi, you will get the True Demon Ending no matter what flags or choices you made. This is why, if you are aiming for any other ending, you want to avoid doing this.The Labyrinth itself is quite long and complex, and requires defeating multiple Fiends in order to complete. This page is not meant to be a full walkthrough of this labyrinth; those can be found elsewhere on long-established sites. Here are the Fiend locations though:

• Matador - After Great Underpass of Ginza. This is a mandatory fight.
  
• Daisoujou - In Ikebukuro Northeast of Mantra HQ, available after meeting Gozu-Tennoh for the first time.
  
• Hell Biker - On the highway outside of Ikebukuro.
  At this point, you have to see a scene at the end of the 2nd Kalpa with the Riders before you are able to fight them.
  
• White Rider - Near the save Terminal in Asakusa.
  
• Red Rider - Near the save Terminal in Great Underpass of Ginza after beating White Rider.
  
• Black Rider - At room 204B in Shinjuku Medical Center after completing the Obelisk.
  
• Pale Rider - After seeing the scene in Mifunashiro where Futomimi gives a speech, Pale Rider will be in the newly excavated underground in Asakusa.
  
• Mother Harlot - After completing Yoyogi Park, go to the far west side of the park, then into the North room.
  
• Trumpeter - At the front of Yurakucho Station.

For the achievement/trophy hunters out there, you might be wondering if you have to complete the whole game multiple times in order to get the achievement "Lord of Creation", which asks you to see all the endings. Thankfully, as long as you just see each ending, you can get the achievement. You don't have to worry about getting all endings on one save file or anything like that, which would require five or six full playthroughs. That means you can do some save file splitting to get all the endings. It'll still take some time, but at least not whole playthroughs.

Basically, what you want to do is this:

• Trigger the first flags for Musubi, Shijima, and Yosuga. This is required to get each of those endings, but these choices won't lock you into any of them just yet. Triggering the first flags will give you the option to pick these endings later.
  
• Then, you'll want to create a backup save before the end of Yoyogi park. Here is your first branching point, as the choices made to Aradia will determine if you lock yourself out of the Freedom or Neutral endings (depending on which you choose).
  
• From here, you'll need to redo portions of the ending sequences of the game multiple times, changing which flags you trip or not, in order to see each ending. You can be a bit efficient and create other savefiles at other, later branch points, for example in front of the choices made at the end of Amala Temple, Mifunashiro, and Diet Building.
  
• Remember, if you complete the Labyrinth of Amala before the Tower of Kagutsuchi, you lock yourself into the True Demon Ending.