The judgment of the first instance court is modified as follows.

A. Defendant (Counterclaim Plaintiff) is the Plaintiff (Counterclaim Defendant)’s KRW 88,304,571.

A principal lawsuit and a counterclaim shall be deemed simultaneously.

1. The reasoning for this part of the judgment of the court is the same as that of the judgment of the court of first instance, and thus, this part of the facts are cited by the main text of Article 420 of the Civil Procedure Act.

2. The parties' assertion

A. The Plaintiff’s assertion that the instant lease agreement was terminated according to the Plaintiff’s notice of termination on the ground of the Defendant’s delinquency in paying three or more rents.

Therefore, the Defendant is obligated to deliver the instant building to the Plaintiff, and pay 9,876,000 won calculated by deducting 10,000,000 won for lease deposit from 19,876,000 won for overdue rent and restoration of its original state, and damages for delay.

B. Around July 1, 2018, the Defendant is obligated to pay to the Plaintiff the amount calculated by applying the rate of KRW 4 million per month from July 1, 2018 to the completion date of delivery of the instant building.

B. The defendant's assertion that the construction of this case was carried out as shown in the list of construction specifications attached to the building of this case and the list below, and disbursed a total of KRW 81,953,710. Accordingly, the value of KRW 77,543,231 on the building of this case is increased. Thus, the defendant's claim for reimbursement of beneficial costs of KRW 77,543,231 is entitled to claim reimbursement against the plaintiff.

In addition, it is not recognized that the right to claim reimbursement of beneficial costs is not recognized.

The plaintiff is obligated to return the above amount to the defendant, as it has obtained unfair benefits equivalent to KRW 77,543,231, which is an increase in the value of the building of this case.

Therefore, as a counterclaim, the plaintiff is entitled to claim for reimbursement of the most beneficial benefit, and the plaintiff is entitled to claim for reimbursement of the above KRW 77,543,231 as a preliminary claim for reimbursement of unjust benefit.

The detailed contents of the name of the construction are as follows: (a) wooden fluoring, floor construction, pening construction, painting installation, 34,947,567 2 electrical PED installation, such as the installation of a hole’s fluoring fluor, 14,667,470 3 feet and equipment, and installation of a fluor and surface fluor at the gas section; and (b) gas and gas.