A. On March 13, 2013, the Plaintiff loaned KRW 121,740,00 to C with interest rate of KRW 12% per annum and maturity on March 13, 2013 (hereinafter “instant loan”). The Defendant guaranteed C’s obligation to the Plaintiff.

B. On December 12, 2013, the Plaintiff and C settled the principal of the instant loan claims at KRW 97,440,000, and re-determined the interest as KRW 1.5 per month and the due date on October 13, 2015.

[Ground of recognition] Evidence No. 1, Evidence No. 2-1, and purport of the whole pleadings

2. The assertion and judgment

A. As of October 31, 2016 as of October 31, 2016, the principal amount of the instant loan claims remains 85,704,648 as of October 31, 2016, and thereafter, the Plaintiff received an additional payment of KRW 2 million from C on November 15, 2016, KRW 1 million on January 21, 2017, KRW 800,000 and KRW 1 million on February 20, 2017, KRW 6.2 million on March 21, 2017, and appropriated it to the principal amount of the instant loan claims.

Therefore, the principal amount of the instant loan obligation is KRW 79,504,648 (i.e., KRW 85,704,648 - KRW 6,200,00). The amount calculated by adding interest of KRW 19,081,104 calculated on the rate of KRW 1.5 per month from March 22, 2017 to July 31, 2018, which is the period for which the Plaintiff seeks, shall be KRW 98,585,752 (= KRW 79,504,648, KRW 19,081,104). The Plaintiff shall claim against the Defendant for damages for delay from the day after the original copy of the instant payment order was served.

B. 1) On December 12, 2013, the Plaintiff and C re-determined the interest rate on KRW 1.5 per month in settling the principal of the instant loan claim as of December 12, 2013. As such, it extended or aggravated the contents of the principal obligation to the extent that does not lose the identity of the principal obligation. As such, it was between the Plaintiff and the Defendant and the Defendant’s unawareness after the formation of the guarantee agreement between the Plaintiff and the Defendant, it does not affect the Defendant’s guaranteed obligation (see Supreme Court Decision 97Da1013, Jan. 21, 200). Ultimately,