Hm... my first impression is that... this drama containing the age gap and older man younger woman genre. Huehehehehe.... 

pretty sure they are the same age (in drama) in fact at one point she stated she might be older idk about in RL , but to  me a lot of Asian actresses look half their age 

Yes, definitely an age gap. He’s 12 yrs older in real life and I think the actress is actually playing younger than her age in this. She’s just starting out, sharing an apartment with her sister, working part time jobs. He’s a former CEO returning from abroad to mentor his nephew. Definitely an age gap.