She was introduced in episode 7 as a voluptuous Portuguese missionary nun who went out to seek permission to travel the country to help the suffering.

In episode 7, she and her bodyguard Bontenmaru were about to be robbed by bandits until Yoshiharu and Inuchiyo came by to help them.

She is based on real Portuguese missionary Luis Frois who befrended Oda Nobunaga and served as his personal scholar in Gifu castle.
(Source: Anilinkz)