I swear this manga made me smile and laugh A LOT of times. I love how they dealt with different issues on their relationship and still manage to be well communicated with each other. Relationships like this always amaze me when they started falling inlove at a young age then grow old together. It's just beautiful.
Honorable mention:
"No, no, allow me" and present your ass.
Confusing at first but after some realization, it's painful. Imagine how could Youngdo change Giju's life only if they had a chance. Right love at a wrong time.