Solanum III is the head priest of the Man of Zinc religion in Alkubra. He holds high religious and political power in Alkubra region.
As priest, he is allowed the touch and read the original holy books of the church. These books seems to be comic books of the Old World. He seems to be always disponible to preach about the Man of Zinc in Orth's Citadel of Loneliness, and offers services where he retells the stories he reads in the church holy books.
Solanum wears a priest hat and a robe where is written "Truth, Justice and America Only". Solanum and the church understands "America" as the holy land of absolute freedom and incredible abundance, where Man of Zinc lives and there's nothing to be afraid of because Man of Zinc protects everyone who lives there from all sorts of evil.
Solanum has a strong dislike of the Narizians, for understanding that their prophet them teaches to use violence for the sake of violence. For that, Solanum thinks that Narizians are dangerous people and fears their violence to spread across Alkubra.
Solanum seems slavery as evil, but shows tolerance to slavery in Alkubra because Workforce Merchants slavers hold narizians back by hunting them. If the protagonist manages to make the Narizians leave Alkubra, Solanum will banish slavery, making Calvin flee from New Serino and stopping slaves from spawn in Alkubra markets.
Solanum also dislikes the Liberation Army and the Qubba Government, but never states why in any point of the game. There is some hints in the game that points out that Qubba Government pursues people for them religion, like Kukul's father, and this religion apparently is the Church of Man of Zinc.
Solanum likes the Federation, maybe for the Federation support to religious refugees, like Kukul's father. There is some hints in the game that points out that the Federation have its own church of Man of Zinc, but Solanum seems to have no connection with the possible church there.
If the protagonist tells to Solanum about Emilia's baby, Solanum will tell that pretty sure the baby and the baby's father are both demons - the same opinion Orion would have, if the protagonist asked her about it too -. Solanum will then recommend the protagonist to kill the demon and ask professional help to Jacob Fulier, the best demon expert Solanum have ever met.