Warning! Tropes and character descriptions will contain spoilers!
Main Characters (Twenty-Fifth Bam) | Organizations (FUG (Canines), Wolhaiksong) | Regulars (First Batch, Second Batch, Third Batch, Fourth Batch, Fifth Batch, Sixth Batch) | Rankers | Irregulars | Jahad Empire (Great Warriors, Princesses of Jahad, 13 Month Series) | Floor Guardians | Others
A series of Empathic Weapons forged by master blacksmith Ashul Edwaru, and given to a chosen Princess of Jahad. They can range from Cool Swords to Improbable Weapons, but all are very powerful.
- Battle Aura: Wielders of a 13 Month Series weapon can sense the aura of another 13 Month Series weapon if they are used in the general area.
- The Corruptor: As per the true purpose of the Princess system, the 13 Month weapons are deliberately set to make their wielders go mad. Yuri nearly succumbed to this fate on the 43rd Floor, but they succeeded in breaking Garam's sister.
- Empathic Weapon: When ignited, the weapon can take physical form.
- Out of Focus: Similar to the Floor Guardians, their role in the story has taken a backseat for season two, which is understandable considering that the weapons are pretty much the end-game when a Jahad Princess becomes a Ranker.
- They finally make a reappearance when Yuri ignites her 13-Month weapons on the 43rd Floor of Death.
- Plot Device: The 13 Month Series all-together serve as half the key that keeps the door to reach the Tower's 135th Floor locked. The other half is the Jahad rings. And, the Weapons have a role in keeping themselves out of the hands of people who can't join them up... by driving Princesses who try either mad and/or against one another. It seems to be an involuntary function/ curse.
- Sealed Badass in a Can: Every weapon has a soul sealed within them and becomes even more powerful when they ignite.
- Talking Weapon: Weapons are capable of communicating with their users, if they so choose.
- Theme Naming: All of them are named in Korean in the general format 'Color Number Moon' (with Black March being 'Black Third Moon', White February being 'White Second Moon'). Although they are named in Korean through the Lunar Calendar, this is translated to English using conventional Calendar Months (with Undecimber being the 13th).
Ghost of the 13 Months
The spirit of a woman that failed to become a Jahad Princess, and now resides within the 13 Month weapons. Said to have made a promise with Jahad to make sure that the Jahad Princess competition is never able to finish, the ghost goes about taking control of any Princess that manages to ignite more than one 13 Month weapon at the same time. The ghost then forces the Jahad Princess to go on a rampage to make it seem like trying to gather the 13 Months will result in the Princesses going insane.
In the present, the ghost of the 13 Months makes her first appearance on the Floor of Death taking control over Yuri after she ignites the Black March and Green April at the same time.
- Ax-Crazy: Enjoys making the Jahad Princesses fight one another, and goes on massive rampages to make it look like the Princess went insane after igniting two 13 Month weapons at the same time.
- Demonic Possession: When a Jahad Princess ignites more than one 13 Month weapon at once, the ghost steps in to take control of said Princess.
- Driven by Envy: Due to failing to become a Jahad Princess, the ghost came to resent those that did, and now torments those that try to obtain more than one 13 Month weapon.
- The Plan: The ghost helps Jahad stay in power by making sure that the Jahad Princesses are never able to obtain more than one 13 Month Weapon. Those that do, the ghost takes control over the Princess, and goes on a rampage to make it look like igniting more than one 13 Month results in the Jahad Princess going insane.
Silver January
Status: Owned by An Jahad
Currently carried by a Princess of Jahad.White February
Status: Owned by Jahad
Granted to a Princess who was killed by Eurasia Enne Jahad when she went berserk. Currently in the possession of Jahad himself.Black March
Voiced by: Shizuka Itō (Japanese), Laura Post (English)
Rank: B-Rank
Status: Absorbed by Twenty-Fifth Bam
Type: Needle
Originally given to Yuri Jahad, the Black March changed owners when she decided to help Bam with his 1st Floor test. It is a sleek black needle (a stabbing tool) with a self-confident, hedonistic attitude. She did not even talk to Yuri because they were alike, but heeds Bam's call, because he is cute. note
During Bam's 2nd Floor journey, the Black March is taken away by Anaak after Bam lost a wager during the Crown Game and was then used by Endorsi in the fight against Ren. Yuri interferes in said fight, drives Ren away and takes back Black March near the end of season 1. Since then, Black March has remained in Yuri's possession, and is finally brought out again on the 43rd Floor of Death.
- The Bus Came Back: Black March, and its spirit, are finally seen again when Yuri attacks Hell Joe's castle on the 43rd Floor of Death.
- Curtains Match the Window: Yellow-eyes with yellow-hair.
- Foil: Turns out she doesn't much want to ignite for, or just plain talk to, Yuri. Bam? Sure! No prob! The more the Weapon and the Princess bicker upon this coming out, the more you realise it's basically because they're way too very similar in a lot of very headstrong ways.
- Jerk with a Heart of Gold: Abrasive, condescending, quick to insult... But, she actually doesn't want to harm Yuri, and talks April into a plan to try limiting the damage of Ms. Too Headstrong's not listening.
- Put on a Bus: Yuri took Black March away at the end of the Submerged Fish Hunt Test, and it wasn't seen for a long, long while after that.
- Troll: One possible interpretation of her swanning off to have some fun with a cute guy she knew Yuri liked? Trolling her Princess (with a little help from Headon).
Green April
Rank: B-Rank
Status: Owned by Ha Yuri Jahad
Type: Hook
Anaak's green hook weapon that originally belonged to her mother. Green April can expand, and split into several hooks at the hilt. In season 1, Green April is never seen talking, but seems to be insane and bloodthirsty. After rescuing Anaak from Ren, Yuri takes Green April away from her near the end of season 1.
Since then, Green April has remained in Yuri's possession, and is finally brought out again on the 43rd Floor of Death. In addition, Green April's spirit finally makes its first full appearance here.
- The Bus Came Back: Green April is finally seen again when Yuri attacks Hell Joe's castle on the 43rd Floor of Death. In addition, the spirit of Green April finally makes its first appearance here.
- Curtains Match the Window: Green-hair with green-eyes.
- Improbable Weapon: A hook?
- Morph Weapon: Green April can expand to ludicrous sizes when ignited, and even be used more like a whip than a hook.
- Put on a Bus: Yuri took Green April away along with Black March at the end of the Submerged Fish Hunt Test, and it hasn't been seen since.
- Slasher Smile: One of the few things we see it do◊.
- Uncatty Resemblance: Hmmm. Maybe there's a reason she's attached to the Anaaks Snr and Jnr... She may not take the shape of a lizard-woman upon full igition, but the similarities are striking.
- With Great Power Comes Great Insanity: Implied to be the case with April herself. Well, either this, or losing Anaak Jahad Snr unhinged the Weapon. However, Yuri and other Rankers who realised what Anaak held tended to be of the opinion that she would be slowly driven over the edge herself simply trying to use and control April at her relatively low level. In rebuttal: Anaak Jnr had been paired with April for quite a while before trying to Climb, with surprisingly few noticeable issues. Well, given the usual nature of those with Jahad's blood, at least. It turns out that April really doesn't want to harm people, including idiots like Yuri. She probably occasionally acts like a maniac to not have to.
Yellow May
Status: Owned by Khun Maschenny Jahad
Currently carried by Khun Maschenny Jahad. For an as-of-yet unexplored reason during the Hell Train saga, Maschenny bets her Yellow May for the Green April that's currently in the possession of Princess Yuri.Luminous June
Status: Owned by Alphid Jahad
Type: Sword
Translates as 'Luminous Sixth Moon', one of 3 in the 13 Month Series to not have a specific color. Currently carried by Alphid Jahad.
Indigo July
Status: Owned by Garam Jahad
Currently one of two Series weapons carried by Garam Jahad, the first Princess to possess two of the 13 Month Series, acquired by killing fellow Princess Yuram Jahad.Blue August
Status: Owned by Garam Jahad
Second of two Series weapons carried by Garam Jahad.Dark September
Status: Unknown
Translates as 'Ninth Moon of Darkness', one of 3 in the 13 Month Series to not have a color. Unknown attributes and whereabouts.Red October
Status: Owned by Arie Hagipherione Jahad
Type: Sword
Confirmed to be a sword, currently carried by Arie Hagipherione Jahad.
Golden November
Rank: S-Rank
Status: Owned by Adori Jahad
Currently carried by Adori Jahad, currently highest ranked active Princess of Jahad and joint highest ranked non-Irregular alongside Enne Jahad (ranked 7th in the Tower).Colorless December
Status: Sealed
Translates as 'Twelfth Moon of Nothingness/Emptiness', one of 3 in the 13 Month Series to not have a specific color. Used by Eurasia Enne Jahad, joint highest-ranked Princess and non-Irregular alongside Adori Jahad (ranked 7th in the Tower).- Only the Chosen May Wield: The weapon is rumored to drive the wielder insane if they are not it's destined wielder.
- Sealed Evil in a Can: Sealed along with Enne when she went berserk.
- With Great Power Comes Great Insanity: Rumored to have caused Enne's madness. The spirit of the weapon went insane along with Enne, causing it to be sealed along with her.
Rainbow Undecimber
Status: Unassigned
Type: Arms Inventory
The 13th item of the series.
- All Your Powers Combined: Since it is an Arms Inventory while the rest are weapons, speculation ran for years concerning the result of putting one (or all) of the 13-month Series weapons inside of it. Later on in Season 3, we learn that its true purpose is to act as one half of the key to the 135th floor, with the other half being the rest of the 13 Month series.
- Hammerspace: As with every Arms Inventory, stores other weapons this way when not in use.
- Too Awesome to Use: Is the only item of the 13 Series that has never been given to a Princess.