I recommend the Myeongdong branch of Vance Clinic.

A few weeks ago, a coworker of mine opened a clinic called Vans Clinic near Myeongdong Station. He said that he got botox for 3,900 won and aquifill for 9,900 won, which is incredibly cheap. So I told him to go and take my sister and I to experience it.

I went there thinking, "Is this really true?" and my brother and I each got botox for our forehead and frown lines for 3,900 won (4,290 won with 10% VAT) for one session, and we're still satisfied even after a few weeks.

My sister ended up spending over 200,000 won on several procedures here.