Nicely summed up and analysed... But I will have to disagree with you on the point that Kang wanted Yiyoung to take him to dinner, etc... Because as I understand from his POV series he was merely looking to hook up with Yiyoung and was doing whatever he was doing like playing footsie, etc as a way of flirting. That's why he was surprised to know that Yiyoung had feelings for him. So until that revelation Kang didn't really consider this possibility.
Having said that, since that point he seems to struggle between his business principles of not mixing business with pleasure and suddenly finding himself more drawn to Yiyoung than he would like...
My two cents...
Oops I didn’t mean to say he wanted to take him to dinner. I just meant that he was looking forward to Yiyoung also wanting to establish a connection. But yeah it right xD
I make it a point to not read the entire manhua from start to finish because I still cringe at the mistakes Yiyoung makes and our first impression of Kang as being terrible.
Nevertheless, I decided to go back and reread Kang's past relationship and had come to remember that he was dumped because the other party (the brown haired lady at the bar with the daughter), didn't take their relationship seriously and figured her priorities were her daughter. In other words, Kang was the only one whose feelings were genuine and he felt tossed aside for someone else more important. As a last parting remark, his ex said something along the lines as "date someone younger, like in their early twenties. give the youngsters a chance, blah blah blah". (Well, low and behold Yiyoung who came at that time.)
Point being, we know that Director Kang felt harshly tossed aside because when push came to shove, his ex favored someone else's happiness over his. This is where I think he and Yiyoung are similar in that matter; they both are serious. With the way things are going, Yiyoung might move up big time in the world because he'll be more and more recognized as like some celebrity, and it'll somehow cause Kang to retreat back out of fear for being tossed aside again because he'll think Yiyoung will leave him behind. This is prob in my opinion when Kang went out with Yiyoung (driving lesson date) you see his face turn a bit disgruntled/serious when Yiyoung mentioned he wanted to get to know Director Kang “for the sake of business”. Evidently, Kang secretly wanted Yiyoung to take him out for dinner and places for the sake of wanting to be genuinely interested in him as a person, and not for some personal gain.
Somehow, their relationship right now can be described like some teeter totter game where in one instance we will see Yiyoung make advances, but the moment Kang humors him as well, Yiyoung reverts back to business-like (like that one "date night"). Perhaps this is the reason why this manhua is called "On or Off". They constantly dance and shift into this game of pursue and retreat in both work and off-of-work setting with no strings attached. Let me know what you think about the title. Did I get it right?