The first one that came to my mind was Age of Youth. bUT that might be because i recommend this to literally every person lol. It has romantic comedy elements but there is still some relatable message behind the story that makes you feel like you are not wasting your time so i guess this might be a good story for an extroverted person (also the fact that there is not only one MC makes it easier to relate to the story?)
If your friend wants something with super natural I think Oh My Ghostess is a good pick. I havnt watched it but i think this is really popular + has Park Bo Young and Kim Seul Gi
The last drama that comes to my mind is Reply 1997. It is also one of those dramas i recommend to everyone (and i am quite sucessful!). It is really funny, fast-paced with short episodes and the romance is great. (And if your friend likes it there are 2 more 'seasons' with the same concept :))