1. The plaintiff's claim is dismissed.

2. The costs of lawsuit shall be borne by the Plaintiff.

1. Basic facts

A. The Defendant: (a) lent money to Nonparty C, the father of the Plaintiff; (b) paid money to the Plaintiff’s account at C’s request; and (c) paid money from the Plaintiff’s account in the name of the Plaintiff.

B. On February 7, 2015, C drafted a loan certificate and a letter stating that “The amount of KRW 22,500,000 shall be repaid until February 27, 2015, and the interest shall be paid on the last day of each month” with the Defendant.

[Ground of recognition] Facts without dispute, Gap evidence 1, 2, Eul evidence 1-1, 2-2, the purport of the whole pleadings

2. The Plaintiff’s assertion C borrowed a total of KRW 28,290,000 from the Defendant during the period from January 15, 2014 to April 25, 2014, and the Plaintiff paid KRW 67,740,000 in lieu of C during the period from January 20, 2014 to April 20, 2017.

Since the Plaintiff paid interest at the highest interest rate of 25% under the Interest Limitation Act in excess of the principal and interest, the Defendant is obligated to return the amount overpaid to the Plaintiff as well as the delayed payment amount of KRW 37,576,637 to the Plaintiff as unjust enrichment.

3. In a case where either party to a contract has reduced the process of performance by the direction of the other party to the contract, etc. and has directly provided payment to a third party under another contractual relationship with the other party to the contract, the party to the contract may not claim a return of unjust enrichment on the ground that the party to the contract received payment against the third party without any legal cause.

(2) In light of the legal principles as seen earlier, even if a third party with a causal relationship with the obligor directly pays the reimbursement to the obligee, the obligee is deemed to bear the obligation against the obligee even if the obligor was aware that the obligor did not bear the obligation against the obligee, and thus, the obligee directly pays the reimbursement to the obligee.