Part two of the coffee stain collection. 

No matter how many times Doojoon tries to engage Hyunseung after the lady's visit, Hyunseung refuses and withdraws himself away from Doojoon. Although Doojoon repeatedly comes by and asks Hyunseung questions, and tries to make things go back to the way it was before, Hyunseung never quite followed. Gone were the days where Hyunseung even sat down with him and enjoyed a cup of coffee. 

Doojoon is confused and upset at Hyunseung's behaviour. After all, a coffee stain shouldn't ever be able to be removed.