This study uses James Donovan's object relations couple therapy to examine the triangle of focus (conflict style, couple characteristics, and family of origin) and triangle of conflict (anxiety, defence mechanisms, and hidden emotions) of a married Korean man with sexual dysfunction (reduced sexual desire, premature ejaculation, and erectile dysfunction). This qualitative study uses thematic analysis to identify, describe, and analyse a family therapy case study. The aim of this study is to examine the couple's interaction patterns and experiences of conflicts related to the husband's erectile dysfunction. The researchers induced patterns or topics by repeatedly reading and comparing the data. Then, they textualised and analysed the relevant data. To ensure the reliability and validity of the data analysis, the researchers conducted shared coding sessions to review and discuss the initial codes and the generated main themes and subthemes, triangulating the qualitative data. Findings show that a newlywed husband's sexual dysfunction is associated with his emotional resistance towards his wife's unilateral pursuit over their sexual relationship and the negative emotions triggered by their dysfunctional interactions. Further, couple characteristics, conflict style (dysfunctional interactions), and family‐of‐origin factors (transference and patrilocality) influenced their sexual relationship. Therefore, therapists who counsel Korean couples with sexual issues may pay attention to the sociocultural factors, interactional patterns, and psychological factors associated with unresolved issues with their families of origin.