So... the formula is making the readers angry?
Kind of. ^_^
But not willingly. Let me give you an analogy. You know the Brontë sisters, Charlotte, Emily and Anne? This a short comic about them:

When it comes to romantic literature for women by women, one of the oldest plot devices in the book is making the heroine's love interest an extremely problematic person: a violent man, an alcoholic, an outcast, a social climber who won't marry the heroine because she's poor, an emotionally-scarred wretch, etc. etc. The story then tells us how the heroine, through great pain and effort, redeems this person's wrongs with the power of her love and wins herself a happy romantic end. Emily and Charlotte Brontë were very fond of this sort of problematic characters, while Anne was NOT; that's why she and her sisters bicker in the comic, as their reactions to the men they see (who by coincidence happen to be the mcs of some novels by Charlotte and Emily) are completely different.
This manga follows that old and tested plot, giving the heroine Ayaka a majorly problematic love interest in Hiroko. Normally, all the readers should react like Charlotte and Emily Brontë would... that is, they should be rooting for Ayaka to break Hiroko's defenses, make her see the errors of her ways, and finally win her heart! Trouble is, 90% of the readers are reacting like Anne would... that is, they think Hiroko is a slimeball and Ayaka needs to find herself a better lover. Ooops. This is not what Sal Jiang had in mind when she created Hiroko.
In the past, there have been many series with similar premises that made the readers in Dynasty forum react the way the author expected. This manga failed to accomplish that. I won't attempt to explain why. Let's just say that Hiroko doesn't have what it takes to charm the readers (whatever this elusive quality may be) and leave it at that.