This age thing I find really interesting and loved that I didn't see it coming at all. Love a good plot twist. He is 18 (international age)/19 (Korean age) prob very close to turning "20" come 1 Jan 2021 anyway. Jun hasn't taken advantage of the lie in any physical sense and I am really enjoying the juxtaposition of his maturity vs her immaturity. I think it works well to turn preconceptions of "age" and how people are stereotypically supposed to act/behave on its head. So I am not bothered at all. He has proven his metal so to speak and is more mature than RaRa is, due to her sheltered life.