1. The defendant's appeal is dismissed.

2. The costs of appeal shall be borne by the Defendant.

3. Paragraph (2) of the decision of the court of first instance.

1. The Defendant asserts that the lawsuit of this case brought by the Plaintiff without standing to sue is unlawful, since the Plaintiff entered into a goods contract with C, not the Plaintiff, but the Plaintiff’s husband, in this case seeking payment of KRW 16,631,900 for the unpaid goods while the Plaintiff manufactured and supplied the Defendant with the Ji government High School’s School (Seoul High School) to the Defendant.

On the other hand, in a lawsuit for performance, the plaintiff's standing to sue who asserts himself/herself as the person responsible for performance, has standing to sue and who is asserted as the person responsible for performance, and the plaintiff's standing to sue itself, and the plaintiff's assertion itself does not require that the plaintiff is the person responsible for performance or the defendant is the person responsible for performance (see, e.g., Supreme Court Decisions 75Da1676, Aug. 23, 197; 94Da14797, Jun. 14, 1994). The above grounds of the defendant's assertion are merely grounds for determining the existence of a claim within the merits, and they are not grounds for determining the existence of a standing to sue before the merits. Thus, the defendant's prior defense on the merits is without merit.

2. Judgment on the merits

A. Comprehensively taking account of the overall purport of Gap evidence Nos. 3 and 6’s written evidence and all pleadings as to the cause of the claim, the Plaintiff determined an unfair unit price of KRW 17,500 between the Defendant and the Defendant around October 2014, and “the supply contract of the instant case for the printing and production of the 2014 graduates.”

(2) In light of the above legal principles, barring any special circumstance, the Defendant shall pay to the Plaintiff damages for delay calculated at the rate of 15% per annum as stipulated in the Act on Special Cases Concerning the Promotion, etc. of Legal Proceedings, etc. from May 28, 2015 to the day of full payment, which is the day following the delivery of a copy of the complaint of this case and the day of full payment. The Defendant shall pay to the Plaintiff damages for delay calculated at the rate of 15% per annum as stipulated in the Act on Special Cases Concerning the Promotion, etc. of Legal Proceedings, etc., from May 28, 2015 to the day of full payment.