Ananda

Ananda is the half-brother of Devadetta as mentioned briefly in book 3. A former criminal who becomes one of Buddha's major disciples. The devil Mara protected him after Ananda's father offered him in exchange for sparing his life. Following his mother's murder, Ananda seeks revenge on all humanity until Buddha saved his life. Ananda then becomes Buddha's personal attendant and companion although visions of hell and death continue to haunt him. (Source: Wikipedia)