A. On September 1, 2015, Defendant Samhwa integrated Construction Co., Ltd., a contracting party to the construction of the instant construction project, ordered Defendant Samhwa integrated Construction Co., Ltd. to undertake the construction of new C, and again Defendant Sam Tae integrated Construction Co., Ltd., a contracting party to the construction of reinforced concrete and installed construction during the instant construction project at the cost of construction from September 1, 2015 to December 15, 2015, the construction cost of which was KRW 640,000,000.

(hereinafter referred to as the “instant subcontracted construction”). B.

Plaintiff’s lease and B’s letter of guarantee 1) The Plaintiff loaned KRW 80,000,00 to B on September 21, 2015, with a maturity of KRW 20% on December 20, 2015 and interest rate of KRW 3% on December 20, 2015 (hereinafter “instant loan”); and the said KRW 80,000,000 “instant loan”).

) (The instant loan was divided into KRW 32,800,000 on September 21, 2015, and KRW 32,800,000 on October 8, 2015, and was remitted to B’s account, respectively.

2) At the time of the instant lease, B issued to the Plaintiff a letter of payment guarantee with the same content as the attached Form (hereinafter “instant letter of payment”).

[Ground of recognition] Facts without dispute, Gap evidence Nos. 1 through 3, 8, Eul evidence Nos. 3 and 4, the purport of the whole pleadings

2. The parties' assertion and judgment

A. The Defendants asserted as the Plaintiff jointly and severally guaranteed the obligation to return the instant loan through the instant guarantee certificate at the time of the instant loan, and thus, they are jointly and severally liable with B to pay the Plaintiff KRW 80,000,000 and delay damages therefrom.

B. Determination 1) The Defendants did not dispute that the Defendants guaranteed the obligation to return the instant loan through the instant guarantee guarantee (the Defendants: (a) have led to a confession of the said guarantee, but revoked it on the second date for pleading of the first instance trial; (b) there is no evidence to support that the said confession was contrary to the truth and due to mistake; and (c) there is no validity of revocation of the said confession.

(2) However, the Defendants’ above guarantee (hereinafter “instant guarantee”).