1. The Defendant’s KRW 56,376,00,00 for the Plaintiff and KRW 6% per annum from June 1, 2016 to November 17, 2017.

1. Basic facts

A. On January 16, 2015, the Plaintiff entered into a construction subcontract (hereinafter “instant construction contract”) with the Defendant on the construction cost of reinforced concrete C (hereinafter “instant construction”) as KRW 494,665,00 with respect to the instant construction work among the instant construction works that were supplied and demanded by the Defendant between the Defendant and the Defendant, and concluded the instant construction contract (hereinafter “instant construction contract”). The Plaintiff completed the instant construction work by March 10, 2016.

B. The construction cost that the Plaintiff received from the Defendant by May 12, 2016 is KRW 416,040,770 (the amount included in the payment of construction cost of KRW 4 million out of the cost of other workshops to be borne by the Plaintiff).

[Ground of recognition] Facts without dispute, Gap evidence Nos. 1 through 4 (including paper numbers), Eul evidence Nos. 2 and 3, the purport of the whole pleadings

2. The parties' assertion

A. (1) As to the construction cost of this case, the Defendant’s original construction contract was intended to be entered into with D, and the actual construction cost was set at KRW 75,000 per square year, and the actual construction cost was set at KRW 20,000 per square year for D (or E), and the Defendant prepared a written construction contract for construction cost of KRW 95,000 per square year, and the Defendant directly paid the introduction fee to D (or E). Accordingly, the construction cost of this case determined by the Plaintiff and the Defendant is KRW 390,525,000 per square year multiplied by the construction cost of KRW 75,00 per square year in 5,207. The portion in excess of the above construction cost is null and void in violation of good customs and other social order.

(2) The Plaintiff and the Defendant concluded the instant construction contract by setting the contract price as KRW 95,00,000, and the introduction cost was not directly paid by the Defendant.

B. (1) As to the portion of the deduction, the Plaintiff incurred 13 months during the construction period of this case, since the cost of other company, which the Defendant (A) borne by the Plaintiff, is not a KRW 500,000 per month, but a KRW 1 million per month.