1. The plaintiff's claim is dismissed.

2. The costs of lawsuit shall be borne by the Plaintiff.

1. The plaintiff's assertion

A. On April 2006, the Plaintiff, the Defendant, and C agreed to jointly invest KRW 800 million in the first floor G, H, and I (hereinafter “instant commercial building”) of the F building in the event of the strike sold by D (E) (hereinafter “E”), and the instant commercial building was sold in the name of the Defendant (the investment amount was KRW 10 million, KRW 60 million, KRW 310 million, KRW 100,000), and the instant commercial building was sold in the name of the Defendant.

B. However, around 2008, D suffered losses not acquired the commercial buildings of this case due to the bankruptcy of D, notwithstanding the payment of their respective investment charges, at the wind of auction.

C. The Defendant asked the Plaintiff to compensate for the investment amount of KRW 600 million by asking the Plaintiff for the liability erroneously introduced to the Plaintiff. The Plaintiff in large amount borrowed KRW 600 million from J (the Plaintiff’s mother) on May 30, 201 and paid it to the Defendant.

However, the above investment was made by the defendant's own decision-making, and the failure of the investment was not caused by the plaintiff's fault, so the plaintiff was not obliged to pay damages equivalent to the investment amount to the defendant from the beginning.

E. Meanwhile, around July 2013, the Plaintiff received KRW 95 million from K (D’s children) as compensation for damages.

(1) The Defendant is obligated to return to the Plaintiff unjust enrichment amounting to KRW 5 billion (=60 million - KRW 95 million) and damages for delay stated in the purport of the claim against the Plaintiff, on the ground that the Defendant had already been fully compensated for the damages amounting to KRW 60 million.

2. On May 30, 201, the fact that the Plaintiff paid KRW 600 million to the Defendant on May 30, 201 is not a dispute between the parties, but the Defendant appears to have invested KRW 600 million in the instant commercial building around April 2006, and it is difficult to believe it as it is, in light of the fact that the Plaintiff and the Defendant did not have written a disposal document, such as the investment agreement or the investment share agreement, between the original Defendant and C.