1. The plaintiff's appeal is dismissed.

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

The purport of the claim and appeal is the purport of the appeal.

1. The Plaintiff Company’s assertion that the Plaintiff Company entered the Plaintiff Company on September 2014 and received basic pay, allowances, etc. exceeding the amount of wages under the annual salary contract until the Plaintiff Company retires from the Plaintiff Company on November 2016, and received 20,627,360 won in total, by receiving separate payment for the amount of taxes and the amount deducted from the Defendant’s insurance principal’s share, and received 773,050 won in total, annual allowances, and 3,100,458 won in excess of 1,784,655,518 (=20,627,360 won, 77,050 won, 3,050 won, 10,458 won, 650 won in total, and 26,285,518 won in total, which the Defendant paid to the Plaintiff Company. Accordingly, the Defendant paid for delay damages to the Plaintiff Company’s claim.

2. Determination

A. The Plaintiff asserted that the Defendant entered into an annual salary contract of KRW 36 million at the time of entry and received benefits in excess of the above annual salary although there was no change in the annual salary. Accordingly, the Defendant, at the time of entry, agreed to pay taxes and the amount to be paid to the Plaintiff at the time of entry, and agreed to pay a holiday allowance at the time of the change in the annual salary over 2 and 3 occasions, and only received benefits according to the changed annual salary. The Plaintiff asserted that the Defendant did not have any legal ground for return of unjust enrichment. The burden of proving that there was no legal ground for return of unjust enrichment in the case of the so-called unjust enrichment of return on the ground that one party made a certain benefit according to his/her own intent and demanded the return of benefits on the ground that there was no legal ground for the payment (see, e.g., Supreme Court Decision 2017Da37324, Jan. 24, 2018; and the Plaintiff’s agreement on the return of unjust enrichment and the Defendant’s testimony as the Plaintiff’s witness should be proved.