1. Revocation of the first instance judgment.

2. The plaintiff's claim is dismissed.

3. All costs of the lawsuit shall be borne by the Plaintiff.

1. The following facts of recognition are acknowledged, either in dispute between the parties or in combination with the purpose of the entire pleadings, either in Gap evidence 1, Eul evidence 1 and 6:

A. On March 11, 2017, the Defendant contracted to C (hereinafter “C”) for remodeling construction of Seongbuk-gu Seoul Metropolitan D Building with KRW 950 million.

(hereinafter “instant prime contract”). B.

The Plaintiff completed the construction of urban gas facilities among the remodeling construction of the said D Building and completed around September 30, 2017. During that process, the Plaintiff spent KRW 21,740,630 of boiler costs, and KRW 5,148,00 of boiler connecting construction costs. Of these, the boiler costs were paid KRW 10 million from the net G where C’s representative director was the Plaintiff.

C. Meanwhile, the written contract for construction work made between the Plaintiff and the Defendant as of June 19, 2017 (No. 1; hereinafter “instant contract”) states that the Defendant gave the Plaintiff a contract for the construction work of urban gas facilities related to the said D building with the cost of construction KRW 67 million (value added tax separate). At the time when the said contract for construction work was made, the term “construction contract amount” was blank, but thereafter, the Plaintiff added “67 million won” to the “construction contract amount” column.

2. The parties' assertion

A. The Plaintiff and the Defendant concluded a contract between the Plaintiff and the Defendant under which the Defendant contracted to the Plaintiff for the construction of urban gas facilities during the remodeling of the said D Building, and the Plaintiff completed the construction of urban gas facilities around September 30, 2017. Under the said contract, the Plaintiff sought payment of the said construction cost of KRW 73,70,000, and the said construction cost of KRW 11,740,630, and the unpaid boiler costs of KRW 140,630, and KRW 5,148,00,00 (= KRW 73,70,000, KRW 11,740,630, KRW 5,148,00) and damages for delay.

B. As to this, the Defendant entered into a contract for remodeling construction of the above D Building including urban gas facility construction with C around March 2017, and between the Plaintiff and the Plaintiff.