If you are referring to the anime/manga " More Than a Married Couple, But Not Lovers " (which features a character named

: The storyline explores the emotional erosion of their marriage. While Maris begins as a loyal partner, the plot heavily features "NTR" (Netorare) elements—a subgenre of adult media focused on infidelity—where Maris is gradually seduced or coerced by other male characters. Key Characters and Their Roles

: The ending often reflects on the permanence of these "circumstances," exploring whether Mari finds a new sense of self or remains trapped in her domestic role.