It is a boss- employee romance.
But let me warn you for the process of romance development.
The mafia boss, Kinn was already feeling something for his bodyguard, Porsche and so when one day his bodyguard gets kidnapped and he finds him at an unconscious state(he was drugged) with bite marks all over his body(attempt of rape) while trying to take care of him, he gets uncontrollable and fucks him, well RAPE him.
And their love develops from this point.
I mean, are you kidding me?! How can some one fall in love with their rapist???? And how can it be normal?
Oh oh moreover, at this point of time Porsche was straight and Kinn was gay. ?
On kinn's defence ( well this is from the book, I dont remember the drama scene), kinn asked for poreche's consent for sex. Well he asked for consent from a drugged person and that's supposed to make sense?
And he also apologised after the incident, which made it all better????

This is not the only scene that calls for trigger warning but the whole show is filled with it.
• Vegas- Pete relationship could have been portrayed normally but who wants it to be sober?
What was their relationship? Was it Stockholm syndrome or Lima syndrome?
• so Kinn and Porsche are step cousins
Well the fans of 'Clueless' movie will love it ?

And there are many more......

I watched the drama 1st and then read the book, the book is worse. English translated book 1 is what I read, and almost every sex between Kinn and Porsche was forced. Kinn forcing Porsche, and it is supposed to be romantic?!