1. The Plaintiff (Counterclaim Defendant) paid KRW 11,311,580 to the Defendant (Counterclaim Plaintiff) and its related amount from March 16, 2012 to December 18, 2012.

1. Facts of recognition;

A. On October 4, 2011, the Plaintiff and the Defendant concluded a construction contract that constructs a new house on the ground C at Jeju-si with the construction cost of KRW 125,00,000,000 and the construction period from October 6, 201 to February 2, 2012 (new sections). The Defendant paid to the Plaintiff the construction cost of KRW 80,000,000 in total over several occasions from October 4, 201 to December 20, 201.

B. The Plaintiff, upon completion of a new construction project of a detached house under the said construction contract, did not agree with the Defendant regarding the issue of payment of the construction cost and the payment of additional construction cost, etc., and requested the suspension of construction work and the payment of additional construction cost, etc. on December 2012. The Defendant notified the Plaintiff that the construction contract will be terminated in the event that the construction is not resumed to the Plaintiff on January 2012.

C. The construction cost is KRW 68,089,00 for the construction cost of the said new house constructed by the Plaintiff, and the public charges paid by the Plaintiff on behalf of the Defendant to Jeju Special Self-Governing Province, etc. is the total amount of KRW 59,420 for the Plaintiff.

[Ground] There is no dispute, according to Gap evidence Nos. 1 through 9, Eul evidence Nos. 1 through 11 (including provisional number), appraiser D's appraisal results, fact-finding reply to the E-building office of this court, and the purport of the argument as a whole, the plaintiff is obligated to return for unjust enrichment the remainder of KRW 11,31,580, which remains after deducting KRW 68,089,000 for the construction cost which was paid to the defendant from KRW 80,000 for the construction cost which was paid to the defendant and KRW 59,410 for the substitute payment.

2. The determination of the Plaintiff’s assertion is the cause of the principal claim. The Plaintiff unilaterally, at the Defendant’s request, did not pay the additional construction cost of KRW 3,200,00, the additional construction cost of KRW 200,000, the additional construction cost of KRW 50,000, the alternative construction cost of KRW 59,420, and the additional construction cost of KRW 59,420, and the additional construction cost of the substitute payment under the temporary suspension of construction.