The plaintiff and C are legally married couple who completed the marriage report on November 17, 2004, and have two children between them.

B. From April 2016, the Defendant knew that C had a spouse, developed from around April 2016 to the relationship of internal relations, and became fully aware of the fact that C had a spouse.

C. The Defendant and C committed an unlawful act, such as having a tourd, and also committed an unlawful act at multiple times, or at the Plaintiff’s residence.

Husband and wife shall live together, and have the obligation to support and cooperate with each other.

(Article 826 of the Civil Act). Husband and wife, as a community combining mentally and physically, shall have the duty to cooperate comprehensively between themselves in order to maintain marriage as a marital community by cooperating and protecting each other, and shall have the right to such obligation.

As such, as the content of the marital or marital life maintenance obligation, the married couple bears the sexual duty that should not commit any unlawful act.

Accordingly, if one side of the married couple commits an unlawful act, it becomes a ground for judicial divorce pursuant to Article 840 of the Civil Code, and one of the married couple is liable for damages caused by a tort against mental suffering that the spouse suffered.

On the other hand, a third party shall not interfere with a married couple’s community life, which is the essence of the marriage, by intervening in a marital community of another person and causing the failure of the marital community.

In principle, a third party's act of infringing on a couple's communal life falling under the essence of marriage or interfering with the maintenance thereof and infringing on the right as the spouse's right to it and causing mental pain to the spouse shall constitute a tort.

Supreme Court on November 20, 2014