Who is Hannah in the novel, The Wives?

Hanna Ovark, whom Seth gives the code name Monday, is Seth’s second wife. Thursday believes that Seth married Hannah only because he wanted children. She does not realize that Seth is legally married to Hannah.

Thursday becomes concerned about Hannah when she sees bruises first on Hannah’s arm, and then on her face. Hannah admits to Thursday that she got pregnant because her husband hid her birth control pills. Hannah invites Thursday to dinner and a movie one day while Thursday is in Portland. Seth texts Hannah during the dinner and warns Hannah that she is having dinner with his mistress. He tells Hannah that Thursday is stalking her and that she should leave.