Who is Dr. Sipes from The Persian Pickle Club and what is their importance?

Dr. Sipes is the town physician, a friendly efficient man who, out of compassion for her loneliness and need arising from his own spends time every day with Forest Ann. Whether the relationship is sexual is never made clear, but the members of the Persian Pickle Club clearly view it, and the pleasure it brings both Sipes and Forest Ann, as more important than any morally defined rules of behavior. There is also the sense that Sipes is, at least to some degree, in on the secret about the death of Ben Crook.