Twenty (2015)

Kang Ha Neul and Jung So Min reunion. Both also played love interests.
Both are romantic comedy movies.

If you'll like one then you'll definitely like the other! It's both about friends and has the same kind of humor, especially the slow motion fighting part resembles each other! Sunny is a bit more serious though :)

Both have similar comedy in them. Both offers a great laughs and secondhand embarrassment.

Both feature three males attempting to lose their virginity - only one of which has a steady girl friend.

Both have pretty similar humor

Characters in Explicit Innocence are a year younger (finishing high school) than those in Twenty but they are around the same level of maturity and state of attempting figuring out their lives.

Both are about close friendship and how those friends experience relationships, college, and life in general.

The main characters in both the drama and movie navigate relationships at the age of twenty and on a college campus. The plots are very different but a good watch if you're looking for the college youth theme.

This drama is from the same director of the movie and it's about three women in their 30 trying to make it in live.

Both stories involves teenagers and they struggles to.... Have sex .both funny and with great actors

This knee-slapping comedy follows a unique story about three friends, Chi Ho, Dong Woo, and Gyung Jae. Each of them has just turned 20 years old and the world is their oyster. With new opportunities, they can do what they want, love who they want, and even, cause a little havoc here and there.

Both center around coming of age tale of men in realistic and satarical way of love, friendships and betrayal.

Both mature themes and content for older audiences with a good balance of romance and comedy. Really relatable and slice of life with great casting.
Twenty is more focused on the bromance between the best friends than their individual romances whereas My P.S. Lover is about the main characters development but still shows their respective friendship circles and their own friendships are still portrayed with good chemistry.
Really enjoyed both!!!

Eulachacha Waikiki and Twenty are both centered around friendship and brotherhood. Both are also very funny and contain a romance aspect.