Matoi Ryuuko's primary weapon in Kill la Kill. She wields one half of a red pair of scissors capable of cutting apart Goku Uniforms. The Scissor Blade can shrink into a regular-sized scissor half, or morph itself via mechanical joints into a much larger version that Ryuuko uses to fight, which she calls Decapitation Mode.
The other half is with the person responsible for murdering Ryuuko's father. She battles Kiryuuin Satsuki and her minions to find out who owns the missing Scissor Blade.
In episode 12, Harime Nui reveals that she owns the other half of the Scissor Blade and that she murdered Ryuuko's father on Kiryuuin Ragyou's orders. For some reason, Nui's half is colored purple until Ryuuko recovers it and reattaches it to her own half.