1. The Defendant (Counterclaim Plaintiff) B and the Defendant (Counterclaim Plaintiff) C are jointly and severally liable to the Plaintiff (Counterclaim Defendant) for KRW 90,870,865.

1. Basic facts

A. On July 7, 2014, the Plaintiff and the Defendant Company entered into a contract for construction works with each of the Defendant Company (hereinafter “instant contract”). On July 7, 2014, the Plaintiff entered into a joint and several guarantee for the Defendant Company’s debt owed by the Defendant Company to the Plaintiff in relation to the said contract (hereinafter “instant contract”). On July 7, 2014, the Plaintiff entered into a contract with Defendant C for construction works with respect to interior works, building works, building works, installation works, electrical construction works, etc., with the construction cost of KRW 1 billion (in addition to value-added tax) and from July 21, 2014 to March 21, 2015 (hereinafter “instant contract”). As of the instant one contract, the Plaintiff entered into a contract with each of the Defendant Company for construction works with respect to interior works, waterproof works, aesthetic works, and other construction works (hereinafter “instant contract”). From July 21, 2014 to December 31, 2014, each of the instant contracts for construction works (hereinafter “instant”).

3) On March 18, 2015, the Plaintiff entered into an alteration contract with the Defendant Company to extend the construction period of the instant one contract by April 30, 2015, on the grounds of lack of air due to rain. (b) On April 10, 2015, the Defendant Company entered into an indemnity insurance contract with the Defendant Mutual Aid Association to guarantee the obligation of defect repair to the construction works under the instant one contract, setting the warranty amount of KRW 33 million, the warranty period and the warranty period from April 10, 2015 to April 9, 2016 (hereinafter “instant warranty liability contract”). The key contents of the warranty liability agreement attached to the said contract are as follows: (a) the Defendant Mutual Aid Association (hereinafter “Union”) under Article 1 (Guarantee Liability) of the Terms and Conditions for Repair of Defects (hereinafter “contractor”) after undergoing inspection on the entry or inspection on the front of the construction works, etc.