1. The Defendant and the Defendant (Counterclaim Plaintiff) jointly and severally agreed with the Plaintiff (Counterclaim Defendant) to KRW 19,715,890, and the Defendant against this.

1. Basic facts

A. On August 14, 2013, the Plaintiff entered into a contract for the supply and installation of household units with the Defendant C, which was newly built by Taedo Construction Co., Ltd. and the said company (hereinafter “instant apartment units”). On August 14, 2013, the Plaintiff entered into a subcontract with the Defendant C on the same terms and conditions as the following. Around that time, the Plaintiff entered into a subcontract with the Defendant B.

Total price: KRW 6,670,000 per week: KRW 29,40,00 per week; KRW 22,2550,000 per annum; KRW 9,80,00 for a new kitchen; KRW 280,000 per week; KRW 120,000 for a new corridor funeral; KRW 80,000 for a new corridor funeral; KRW 6,67,000 for a contract date for the payment of KRW 40,00 for a new corridor funeral; KRW 13,334,00 for a household body of KRW 70,00 after construction; KRW 13,34,34,00 for a new apartment unit of KRW 168; KRW 13,34,00 for a new apartment unit; KRW 4,000 for a new apartment unit of KRW 4.30,000 after completion of construction; KRW 130,000 after completion of construction; and KRW 130,134,00000 after completion of construction;

On August 16, 2013, the Plaintiff received performance guarantee insurance from Defendant B as the purchase price of KRW 10,000,500, an amount equivalent to 15% of the construction cost, and paid KRW 6,667,00 as the contract deposit to Defendant B on August 20, 2013.

However, the Plaintiff, while starting the instant construction work on September 26, 2013, deemed that only four human resources were considerably insufficient to properly perform the construction work in light of the household size and air of the instant apartment complex, and rejected Defendant C’s request for advance payment, and on this ground, Defendant C refused to implement the instant construction work, and paid KRW 15,334,100 in advance to Defendant B on October 2, 2013 (an advance payment of KRW 13,34,000 in advance, and KRW 20,001,100 in advance (an advance payment of KRW 13,34,000 in advance of the agreement).

(c).