1. The defendant (Counterclaim plaintiff)'s appeal is dismissed.

2. The defendant-Counterclaim plaintiff's counterclaim brought at the trial.

1. Determination on the main claim

A. The reasons why the court should explain this part of the judgment of the court of first instance are as stated in the reasoning of the judgment of the court of first instance, except for adding the following judgments as to the newly asserted matters in the court of first instance. Thus, this part is cited by the main sentence of Article 420 of the Civil Procedure Act.

B. The summary of the additional set-off claim 1) although the size of the leased object stipulated in the instant lease agreement was 142.73 square meters, the area actually provided by the Plaintiff to the Defendant was limited to 88 square meters. Therefore, the Defendant’s aforementioned defense is without merit, on the ground that the rent corresponding to the area of the leased object that the Defendant was unable to exclusively use or make profits due to the Defendant’s absence of possession, and the amount already paid by the Defendant to the Plaintiff is unjust enrichment and should be returned to the Defendant. Accordingly, the Defendant’s claim for return of unjust enrichment against the Plaintiff is offset against the Plaintiff’s claim for return of unjust enrichment. Therefore, as seen in the judgment on the counterclaim claim as alleged by the Defendant, it cannot be deemed that there exists a claim for return of unjust enrichment against the Defendant, as alleged by the Defendant.

C. If so, the plaintiff's main claim is justified within the above scope of recognition, and the remaining claims shall be dismissed as it is without merit, and the judgment of the court of first instance is just and reasonable. Thus, the defendant's appeal is without merit.

2. Judgment on the counterclaim

A. The Defendant’s assertion 1) Although the area of the leased object stipulated in the instant lease agreement was 142.73m2, the area actually provided to the Defendant is 88m2 (24m2 in store of 52m2 in exclusive use area).

Nevertheless, the defendant has paid all the rent under the above contract to the plaintiff. Among the rent that the defendant has already paid to the plaintiff, the defendant occupies.