A. The Plaintiff and C are married couple who completed the marriage report on April 28, 2010, and have two minor children.

B. While the Defendant was employed as an employee of an entertainment shop, the Defendant became aware of the Plaintiff as a guest in 2018, and thereafter became aware of the relationship with C, such as having a variety of sexual intercourses in the Defendant’s house, etc.

[Reasons for Recognition] Unsatisfy, Gap 1, 2, 4, 5, 8, and the purport of the whole pleadings

2. Determination

A. Husband and wife are liable to live together and support each other and to cooperate (Article 826 of the Civil Act). As such, husband and wife’s duty of living together or to maintain both spouses’ communal living, the husband and wife shall bear the sexual duty of care not to engage in any unlawful act.

If one side of the married couple commits an unlawful act, the other side of the married couple shall be liable for damages caused by a tort against the mental suffering which the spouse has sustained.

On the other hand, a third party shall not interfere with a married couple’s communal living which corresponds to the nature of the marriage, such as intervening in a couple’s communal living of another person and causing the failure of the couple’s communal living.

A third party’s act of infringing on a couple’s communal living or interfering with the maintenance thereof and infringing on a spouse’s right as the spouse, which constitutes a tort (see, e.g., Supreme Court Decision 2013Meu2441, May 29, 2015). The act of infringing on a spouse’s right as the spouse is considered an unlawful act here.

“A greater concept, including the adultery, includes all unlawful acts that are not faithful to the husband’s duty of good faith even if they do not reach the common sense (see Supreme Court Decision 2010Meu4095, Nov. 28, 2013, etc.). B. According to the above facts, the Defendant committed unlawful acts with C, thereby infringing upon the husband’s common life of the Plaintiff and C, interfering with their maintenance, and infringing upon the Plaintiff’s spouse’s right as the spouse, thereby causing mental pain to the Plaintiff.