1. The plaintiff's appeal and the conjunctive claim added in the trial are all dismissed.

2. After an appeal is filed.

1. The court's explanation of this case is identical to the part of the reasoning of the judgment of the court of first instance except for adding the same content as that of paragraph (2). Thus, it is acceptable to accept this as it is in accordance with the main sentence of Article 420 of the Civil Procedure Act.

(The findings of fact and judgments of the first instance court shall not be different, even considering the allegations and evidence added in the trial. 2. Additional decision

A. The plaintiff's assertion that even if it is not recognized that the plaintiff completed the construction work under the construction contract of this case, the plaintiff spent KRW 51,242,40 for the construction cost of this case, and the defendant made unjust enrichment without any legal ground. Thus, the defendant is obligated to return the above amount to the plaintiff as unjust enrichment.

B. We examine the judgment, and the fact that the plaintiff acquired the status of contractor for the construction contract of this case from the non-party company and carried out the construction contract of this case with the defendant's consent or ratification is as seen earlier. Since the performance of the contract between the parties cannot be an unjust enrichment unless the relationship between the cause of performance is legally invalidated, the plaintiff's assertion against this cannot be examined further.

3. In conclusion, the judgment of the court of first instance is just and without merit, and the plaintiff's conjunctive claim added at the court of first instance is dismissed as it is without merit. It is so decided as per Disposition.