Yogaitōgane

Yogaitōgane
The grooves along each blade are made to hold a pair of Ignimarks
Type	Weapon
Material	Molten silk-steel alloy
Origin	Jorogumo-forged relic
Status	Unique; currently wielded by Billy Middleton
Danger Level	Extremely High
Notable Traits	Flame-conductive steel, chain-linked dual blades, bondable Ignimark grooves

Yogaitōgane is a legendary dual-bladed weapon in the SLAY series. It is forged from a rare enchanted alloy known as molten silk-steel — a material born of both jorogumo magic and advanced filament-forging techniques. The weapon's most notable feature is its ability to channel "fire that is not fire," making it uniquely compatible with Billy Middleton's destructive magical abilities.

Overview

Yogaitōgane resembles a reinforced staff at rest, but it splits into two short, curved swords joined by a retractable chain hidden inside the hafts. Its blades are grooved to accept a matching pair of long, wand-like relics known as Ignimarks. These artifacts unlock the weapon’s true destructive potential — though Billy is able to use it in its semi-awakened state thanks to his innate dark flame.

Forging Origin

The weapon was originally forged during the twilight of the Jorogumo Wars by a renegade mage named Tsukirei. Tsukirei specialized in flame magic, a rare affinity among her kind. She designed Yogaitōgane not just as a killing tool, but as a channel — capable of cutting through regenerative flesh and magical wards that resisted conventional fire.

Abilities

• Twin blades linked by a filament-core chain
• Grooves in each blade to insert Ignimarks, which unlock full power
• With or without Ignimarks, the blades can conduct "fire that is not fire"
• Can be used as a staff, dual swords, or whip-like chain weapon
• Burns hot enough to melt magical ice, bypass enchantments, or cauterize on contact

Cursed Inscriptions

Each blade of Yogaitōgane bears an ancient warning, engraved in a stylized, archaic dialect believed to predate modern Bastion script. These inscriptions glow faintly in the presence of filament heat, and blaze to full intensity when the wielder channels dark fire through the weapon.

Left Blade

The black flame of Tsukirei consumes all.

• **Archaic Script:** 「継霊ノ黒焔、悉クヲ喰ラウ」
• **Romanized:** Tsukirei no kokuen, kotogotoku o kurau

Right Blade

Those who cannot master the power will be the power’s slave.

• **Archaic Script:** 「力ヲ制セヌ者、力ノ隷ト成ル」
• **Romanized:** Chikara o seisenu mono, chikara no rei to naru

These phrases are etched just above the grooves meant for Ignimark insertion. Some Bastion scholars believe the inscriptions are self-renewing, gradually re-etching themselves when damaged — a trait commonly found in cursed weapons from the Jorogumo War era.

Hidden Socket Lore

Each blade contains a long, narrow groove — currently empty. The grooves are sized precisely to accept a single Ignimark relic. Ancient texts warn that without these, the weapon remains incomplete and unstable: > That which burns without fire shall awaken the coil. But beware—until the fang is fed, the blade drinks only hope.

Known Wielder

• Billy Middleton — Able to wield the weapon thanks to his innate heat-based power. The grooves remain unfilled.

First Appearance

SLAY Season 3, Episode 91