This is troublesome. There's no shame in hitting back regardless of gender, but this is Korea we're talking about so the viewers might not view this as kindly.
So if Hobin fights her and manages to win, he'd get seen as a bully. If he loses, he'd get seen as a wimp. There's no win here.
There's another option, where Gaeul (is that her name?) fights her instead, leading the viewers to treat this as a "cat-fight" (though there's nothing "cat-fight" about people sucker-punching other people's throats). But at the very least, they'd treat it as "fair", since both were female.
Then again, HTF always does something completely unexpected and out of the norm, so I don't expect any of my theories to come true.