A. On August 20, 2014, the Large Name Industry Development Co., Ltd. (hereinafter “large Name Industry”) entered into a subcontract agreement with the Plaintiff by setting the contract amount of KRW 883,300,000 (Advance 110,000,000) and the construction period from August 25, 2014 to June 28, 2016.

B. On August 2014, the Plaintiff entrusted the instant construction work to D Representative E, and the amount of the contract for the operation of E and the construction work is KRW 22,724,842 equivalent to 3% of the subcontract amount, excluding industrial accident, employment, building, long-term care for the aged, pension and retirement mutual-aid installment, out of the amount of the instant construction work, after deducting KRW 22,724,842 equivalent to 3% of the subcontract amount from the Plaintiff’s operating fund, and managing the remainder of KRW 734,470,00 (97% of the subcontract amount). The Plaintiff signed the contract for the operation of the construction work (hereinafter “instant agreement”), and the Defendant, a representative of the F, signed the said agreement as a joint and several surety.

C. On September 1, 2014, the Plaintiff paid to the Defendant KRW 50 million out of KRW 110,000,000,000 which was paid as advance payment, and on September 5, 2014, paid the remainder of KRW 55,00,00 to E at the Defendant’s request, and on the same day from the Defendant, received the said amount as advance payment from the Defendant on September 5, 2014, “The construction period of KRW 10,000,000,000,000 from September 5, 2014 to December 31, 2015, the said amount was received from the Defendant as advance payment, and each of the said amounts was to be returned and compensated when used for any other purpose than the construction works or the performance of the construction works is not carried out (hereinafter “instant letter of performance”).

The Defendant informed E around February 2015, of the completion of the instant construction works, while the construction works among the instant construction works from around December 2014 did not proceed any longer due to the circumstances of Boan-si. The Defendant notified E of the completion of the instant construction works from around April 2015.