|“||Now listen here Musubi, you have to toughen yourself up so you'll keep getting stronger and stronger, just like she was. I want you to become even stronger but I also want to make sure we keep our promise to each other: to become the last two standing and then we can fight each other till the end. Until that happens, let's just keep having fun killing Sekirei.||„|
|~ Karasuba to Musubi|
Karasuba is one of the main antagonists of Sekirei and among the most powerful of Sekirei.
Karasuba still wears the uniform all female members of the first generation Disciplinary Squad were equipped with. A tight black leather top, a miniskirt and stockings, over the shoulders wearing a grey haori with the Sekirei Crest printed on it. She has long light gray hair tied in a ponytail and gray narrow eyes. She is usually seen with bags under her eyes, giving her an exhausted look.
She has a great hatred for the world and has a rivalry with Sekirei number 8 Yume. She finds enjoyment in killing other sekirei which is her way of relaxing. She mantains a cold demenor but gets excited by the idea of fighting strong opponents. She has no regard for life but She will stop herself from killing her rival Yume who rest's inside Sekirei number 88 Musabi to keep a promise she and Musubi both made: to keep fighting till they are the last two Sekirei. Karasuba shows Patience, honesty and encouragement when she's around Musubi.
Karasuba is known as Sekirei number 4 and leader of a group called the 3rd generation Disciplinary Squad.
Abilities and Powers
Karasuba has great strength. Her weapon of choice is a nodachi which has the power to cut through energy/elemental attacks such as wind, water, etc. She is shown to have an incredible speed, able to kill military men in seconds and she is feared by many Sekirei. Matsu once stated that if Miya and Karasuba would engage in a fight, half of Tokyo would be destroyed in the process. During fights with other sekirei, Karasuba often kills them in one move. Unlike Miya, who has been shown to be able to split a battleship with the shockwave from her sword, Karasuba has so far been shown to actually need to make contact with what she is attacking.