She first appeared when Touya and his friends came to the Great Sea of Trees to aid them in the battle against an intermediate class spider Phrase that was attacking their village. Tsubaki is a young woman who appears in kunoichi clothing. Tsubaki has dark purple hair with a red camellia hair pin.
Tsubaki is a loyal and hardworking person who will follow her own sense of morals at all times.
Tsubaki is first revealed during the meeting with Ieyasu Tokugawa and Yae's father concerning the attack on the fortress. When Jūbei states that they don't know which Takeda stronghold in which Yamamoto Kansuke is occupying, she drops in on the conversation from the rafters. Tsubaki carries a message sent from one of Takeda's Elite Four Kōsaka Masanobu telling of the state of affairs within the Takeda territory. She agrees to show Touya and Leen where the stronghold is and becomes the second person whom Touya uses the Recall Spell on. Once they are outside the walls of the stronghold, she escorts them inside to free the three imprisoned members of the Elite Four. Tsubaki is present when Takeda Shingen is brought down by Touya shooting the mask off his face, she is later seen praying for him to rest in peace. Tsubaki is next shown during the rebuilding of the Takeda grounds on a knee next to Baba Nobuharu after Touya asked him about the Niruya Ruins. After Leen's remark about Touya being apprehensive about using Recall on old men, Tsubaki is seen smirking. Tsubaki makes a brief appearance as Touya imagines her in a red bikini and seem quite fond of it.
Tsubaki is next shown when she shows up at the Brunhild Castle to ask Touya again for assistance with an uprising among the other lords of Eashen and the young daimyo Takeda Katsuyori. After the uprising is quelled and the Eashen King removes the Takeda territory from Katsuyori's control, Tsubaki and many of the Takeda soldiers, the Elite Four, and Tsubaki's ninja comrades all emigrate to Brunhild to make up some of it's first official citizens.
Tsubaki is a skilled ninja and uses ninjutsu. She specializes in stealth, espionage, and information gathering.
- While under her invisibility spell Leen sneaks behind Tsubaki and begins groping her and blaming it on Touya.
- Tsubaki can use her ninjutsu to speak to others using cats as a medium.
- Tsubaki is one character whose family name remains unknown.