1. The Defendant shall pay to the Plaintiff KRW 221,356,850 and the interest rate of KRW 15% per annum from May 25, 2018 to the date of full payment.

1. Comprehensively taking account of the overall purport of the pleadings as to the cause for the claim Gap's evidence Nos. 1 and 2, the Plaintiff is obligated to enter into a contract with the Defendant for the supply of building materials, etc. for the construction of detached Housing C from October 31, 2014 to July 2015, and to pay a total of KRW 221,356,850 (including value-added tax). As such, the Defendant is obligated to pay to the Plaintiff damages for delay calculated at the rate of 15% per annum as prescribed by the Act on Special Cases concerning the Promotion, etc. of Legal Proceedings, etc. from May 25, 2018 to the day of full payment, as sought by the Plaintiff.

2. The defendant's argument as to the defendant's assertion is that D, the owner of the above construction work, is jointly and severally liable for payment of the construction material price to the plaintiff, and thus, the defendant's above obligation is exempted. However, barring any circumstances such as the third party's acceptance of the obligation with immunity and the creditor's acceptance, the principal debtor's obligation cannot be exempted solely on the ground that a joint and several surety exists. Thus, the defendant's above argument is without merit without examining the remaining points.

3. In conclusion, the plaintiff's claim of this case is justified and it is so decided as per Disposition.