1. The judgment of the first instance, including the claim of the Plaintiff’s Intervenor added by this court, is as follows.

1. In the first instance trial, the Plaintiff filed a claim for the return of unjust enrichment due to the cancellation of the contract and restitution to its original state, and as a preliminary claim, the settlement amount due to the execution of the security for sale.

The first instance court dismissed the main claim and rendered a judgment citing a part of the conjunctive claim, and only the defendant appealed against the losing part.

Therefore, only the conjunctive claim of the first instance judgment is subject to the judgment of this court.

2. The court's explanation on this part of the facts of recognition is the same as the corresponding part of the reasoning of the judgment of the court of first instance. Thus, this part is cited by the main text of Article 420 of the Civil Procedure Act.

3. Judgment on the plaintiff's claim

A. According to the Plaintiff’s claim, the part concerning the order of seizure and collection regarding the part concerning the succeeding intervenor’s claim is lawful; 1) if there exists a seizure and collection order concerning the relevant legal claim, only the collection obligee may file a lawsuit against the garnishee; and the obligor loses the standing to file a lawsuit seeking performance against the claims subject to seizure (see, e.g., Supreme Court Decisions 9Da2388, Apr. 11, 200; 2010Da4044, Apr. 28, 2011); or (3) the Plaintiff’s evidence evidence Nos. 9, 10, 6, and 7, each of the following facts: (i) on October 10, 2019, the succeeding intervenor’s claim was sent to the Plaintiff by the Defendant, and KRW 500,000,000,000,000 of the money that the succeeding intervenor paid to the Plaintiff; and (ii) on March 14, 2018, the succeeding intervenor’s claim No.