Terai

is a former member of Konohagakure's Anbu faction Root, who took direct orders from Danzō

Background
As a member of Root, Terai was likely trained to lose emotions in order to better accomplish missions. As Root members each uses a codename, it is unknown what Terai's real name is, if he even has one. Even though the organisation has been officially disbanded, Terai remains loyal to its head, Danzō Shimura.

Personality
Terai is a very loyal shinobi that follows any and all orders given to him by Danzō.

Appearance
Terai wears a light-coloured hooded jacket and an Anbu mask on his face. The mask has three eyebrow-like markings above each eye hole and a red cat-like nose. He also wears a pair of black gloves.

Abilities
Terai's ability was considered equal to those of Fū Yamanaka and Torune, the former of which is considered the strongest member of Root.

Five Kage Summit
Before leaving to attend the Kage Summit, Danzō instructed him to find Kabuto Yakushi before Anko Mitarashi, who was doing the same at that point in time.