Lines 

Hee-joo: 유리 아빠... 여자 생긴 거 같애.

I think Jae-hoon is seeing someone. 

Seo-yeon: 뭐라고?

What? 

Hee-joo:     저 인간, 본병 도졌다구. 

하는 꼬라지로 봐선 한 두 달 그쯤 됐을 거야, 아마.

His old habit has surfaced again. 

Looking at the way he’s been acting these days, I think it’s been about a month or two. 

Seo-yeon: 설마... 너희 남편 가정적이잖아.

It can’t be. Your husband is a family man, isn’t he?

Expression of the Week

설마 (It can’t be, (he) would never) 

설마 – adv. really, probably not, but it is possible

Casual – 설마 

Semi-polite/polite – 설마 (그럴리가요)

>>[설마] can be used in a variety of different ways with different meanings but in this dialogue, Seo-yeon is expressing doubt at Hee-joo’s comment about her husband. 

>>With the single word [설마], Seo-yeon is in effect saying “(you must be mistaken) he would never (cheat on you).”

>>Related proverb: “설마가 사람 죽인다(잡는다)” > Blind trust can kill a person. This expression can be used to warn someone to be careful of something that they trust because it may catch them off guard.