Shirabe

was follower of Boro's cult.

Kawaki Arc
Konohamaru and Sai were brought in by Akari to Shirabe and Tsuzumi in order to ask about Boro's whereabouts. Later when Sai and Konohamaru obtained evidence of the hoax that existed in the cult, Shirabe stepped in and explained to all of the other cult followers about Boro's desire of saving people and why they all continue to follow him and his teachings. Before being disintegrated by Delta, he noted that he would continue to wait until Boro appeared again.