It's nice to see IU acting in sync with Byun Woo-seok, the Grand Prince's wife, while facing him.

Even though only Byun Woo-seok appears on screen during the breakup scene, IU is acting right in front of him, matching his emotions.

It's an important scene.

He looks completely immersed, even shedding tears.

Seeing things like this really makes you feel like they are professionals.