1. The plaintiff's claim is dismissed.

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

The Plaintiff asserts that the Defendant had a duty to return to the Plaintiff the actual debt amounting to KRW 124,850,000,000 as unjust enrichment on November 13, 2015, inasmuch as the Plaintiff received the registration of creation of a neighboring mortgage and the registration of creation of superficies on the said land without cancelling the registration of creation of superficies on November 13, 2015, inasmuch as the Plaintiff had the real debt amounting to KRW 124,850,00,000, out of KRW 618,000,000 prior to C, and KRW 134,90,000,000, out of KRW 618,000,000,000, out of KRW 618,000,000.

However, even if the above alleged facts are acknowledged, the defendant did not gain profit by the reason of the repayment, etc. of the amount of secured debt by the plaintiff's assertion against the creditor, and there is no evidence to prove otherwise that the defendant made unjust enrichment equivalent to 124,850,000 won by transferring ownership to the plaintiff without extinguishing the right to collateral security and superficies established on the subject matter of sale and purchase of the land alleged by the plaintiff.

Thus, the plaintiff's claim is dismissed as there is no ground.