Weak Premise all the way. ( Anything above 7 is overrating for this drama)
Starts off with the most suspenseful way but then goes all the way down, with no conclusion other than what's visible.
This drama seems to be tough to digest for female viewers xD
But it's damn interesting at one point.

People don't seem to realize how selfish they can be.
If you're looking for something righteous, don't watch this.
This is a depiction of many of corporate affairs.
The baseline of this drama is the mystery and the outcome it will disclose.

Don't be a butt hurt over a drama and enjoy.
Laugh and see the manipulation in this drama xD
Life isn't your everyday bubbly garden but an ugly mud pool.
Denying the fact that affairs happen and getting butthurt over such things will only make yourself end up in misery.

Although the writer has messed it up in every way, the sole worth of watching this is the affair mystery.
This is a woman-centric drama.
Still, this is one of the rare cases where I'll say the writer being female has totally feigned ignorance to the male protagonist.
He's left like an emotionless bastard, his facial expression are zero.
I wonder how can you write such a sleazy character but nonetheless it went okayish.
I won't go into description coz there's nothing really to talk about, it's what it is if you've read the synopsis and it stays the same till the end.