quick summery: the dude in the car ( mr seo) is a director at the agency where the brown hair guy ( forgot his name) works as an actor. They make a deal where seo is gonna help him with the acting career as long as he finds a usb in his house. Apparently the actors dad used to work for the family of seo and the usb contains proof of how his mom was killed or smth and he was searching for it. They get into a sexual type of relationship and the actor ends up falling in love with him but seo does not want to accept his feelings so he refuses him. The actor finds the usb and returns it to seo( while he mentions it to his dad). His dad is a drunk dude who gambles and takes loans from loan sharks and while he goes to seo's dad to blackmail him for the usb and take some money, seos dad gets him killed. In this part the funeral of his dad is held where the loan sharks come and make a mess of it and seo now want to apologise and maybe get back with the actor. 

sorry its very short with no details but yeah even i dont remember all the details here. Hope it help