Moroha once had a master named Yawaragi, who was keeping a life-threatening secret. In order to resolve the secret and protect her pupil, Yawaragi made an agreement with Jyubei.
You can have the key to that armor of yours, 
 but only in exchange for Moroha's head.
.يمكنك الحصول على مفتاح الدرع، لكن مقابل رأس موروها
Troco a cabeça da Moroha
pela chave da Armadura de Rato de Ferro.