Very Good Visuals - the actors as well as the venue of the story...
But it feels rushed, less development of characters and relationships on a bullet train( all the three involved in the love triangle)
I also feel that something could be done for the other two characters too, other than just letting them be present as fillers.
Also, I feel confused about the starting of the series i.e. the character's mom's advice about good and bad strangers... It didn't have anything much to do with the story.
Similarly, them training in Ju Jitsu also didn't have much to do with the story.
Some points made me feel bad about the third corner of the love triangle, Ji Soo.(I tell this based on the following points)
1. The ml won in Ju Jitsu.
2. At one point I remember Cha Ji Soo mentioning that his father supported/ trusted Eun Kyu more about running the cafe- The Tasty Florida.
3. Ji Soo tells Eun Kyu that he is interested in Hae Won and at the same time Eun Kyu is not very decided about Hae Won. I felt that Eun Kyu should have let them try it out first. To the contrary, he interferes.
4. He wins over Hae Won.
5. He also gets to go and search for his father, just after beginning his relationship with Hae Won.
From these points, from my point of view, Eun Kyu actually got all that he wanted, contrary to what is shown in the show(that he sacrificed everything for Ji Soo). I sympathise more with Ji Soo... That is not to say that the relationship between Eun Kyu and Have Won is not right or not intresting... It's just that it could have been done in a better way...