1. The Defendant (Counterclaim Plaintiff) paid KRW 1,218,450 to the Plaintiff (Counterclaim Defendant) and the Plaintiff’s objection thereto from June 11, 2014 to September 18, 2015.

A principal lawsuit and counterclaim shall also be deemed a principal lawsuit and counterclaim.

1. Basic facts

A. On March 2014, the Plaintiff entered into a contract with the Defendant for the construction of a new house (hereinafter “instant contract”) with the removal of a house built on the ground of Bosung-gun C and the new construction of a new house (hereinafter “instant construction”).

B. From that time, the Plaintiff commenced the instant construction work. The Defendant: (a) KRW 15 million on March 19, 2014; (b) KRW 10 million on March 20, 2014; and (c) KRW 10 million on March 21, 2014; (b) KRW 20 million on April 9, 2014; (c) KRW 10 million on April 10, 2014; (d) KRW 10 million on May 12, 2014; and (e) KRW 50 million on May 13, 2014; and (e) KRW 90 million on May 29, 2014, KRW 90,000 on the account number of the Plaintiff (hereinafter “the instant contract”).

Meanwhile, although the Plaintiff used the instant account for personal purpose, the remaining amount was zero won at the time the Defendant started paying the money.

C. By June 10, 2014, the Plaintiff entered the instant construction work, and the Defendant, around the beginning of June 2014, carried out construction works, such as 1,269,60 won of 21,269,60 won of his own expenses, dyke, attached string, new string, kitchen, toilet kitchen, multi-purpose, electric light, kitchen board, and stairs rail.

The Plaintiff was issued a certificate of completion on June 11, 2014 to an architect E with an inspection certificate on gas completion.

On June 23, 2014, E issued a document related to completion of construction, including a certificate of installation of hot stones and heating tanks, and a written application for completion inspection of septic tanks, and E received a transmission of a completion photograph of septic tanks necessary for usage inspection from the Defendant and received approval from the administrative agency.

E. On July 17, 2014, the Defendant completed registration of initial ownership relating to the buildings listed in the separate sheet.

[Ground of recognition] Unsatisfy, Gap evidence Nos. 3, 4, Eul evidence Nos. 3 and 4, and fact-finding with respect to F architect office of this Court, the purport of the whole pleadings

2. The summary of the parties' arguments.