Who is Sieverance from The Blue Afternoon: A Novel and what is their importance?

Sieverance is an officer in the United States Army. He leads combat infantry and during the timeline of the novel, he is deployed on active duty in the Philippine Islands. Sieverance is married to Delphine Blyth, and he is noted as being sexually impotent. Thus, when Delphine conceives a child, Salvador Carriscant's child—Sieverance is ecstatic. Sieverance is murdered toward the end of the novel.... shot in the head while in bed. His remains are noted as being shipped home to America for burial.