Yutaka (played by Micky Yoochun) and Jang Miri (played by Lee Dahae) meet in the subway and end up hugging each other, drawing the two together. I think it would be safe to assume that Yutaka pulled Jang Miri in to his embrace to protect her from something or someone (a typical Korean drama scene that usually gets multiple replays from different angles).
It seems that later, Yutaka confesses his love to Jang Miri, to which she later scoffs at, because he remains yet a foolish child. However, even her acknowledgment of him brightens up his day.
On a side note, I haven’t seen Yutaka wear a suit with a tie before, and he also seems to fancy cardigans. And I don’t think Lee Dahae has smirked before in the previous dramas that I watched with her.