Sung Deok Im (Lee Se Young) promised Crown Prince Yi San (Lee Junho) that she will protect him and will never leave his side until he becomes the new King. Read more to know what happened in "The Red Sleeve Cuff" Episode 5.

'The Red Sleeve Cuff' Episode 5: Yi San Confesses Feelings to Sung Deok Im

Sung Deok Im was caught following Yi San, and suddenly became a member of their secret group, handled by Hong Dong Ro (Kang Hoon).

The crown prince found out that the court lady was tasked by his mother, Princess Hyebin (Kang Mal Geum), to look after him. Yi San was angry and felt betrayed by the fact that he is her master but followed someone else's command without his approval.

Sung Deok Im begged after the crown prince told her to leave the palace for disobeying him, though she was lucky to be forgiven.

Meanwhile, Yi San's feelings for the court lady starts to grow deeper. He gifted her books to read. He also offered her a free studying session if there are things she can't understand.

Sung Deok Im's heart's fluttered after Yi San confessed that the time they spent together in the library was special to him.

Crown Prince Thinks Sung Deok Im is About to Marry His Majesty

The crown prince decided to walk in the palace garden to clear his mind as he has been preoccupied by the court lady. As he strolled along the garden, he saw Sung Deok Im wearing a beautiful hanbok and rushed towards her.

He mistakenly thought the court lady would marry his grandfather, not until Hong Dong Ro told him all the court ladies were having a dress rehearsal for their much-awaited ceremony.

Yi San realized his mistake and ran out of embarrassment.

ALSO READ: 5 Lee Junho's Dramas That Prove His High-Calibre Acting Skills

Meanwhile, on the day of the court ladies ceremony, Sung Deok Im unexpectedly overheard the crown prince and Princess Hyebin's conversation.

Yi San told his mother he doesn't know any court lady and has no plan of engaging with them. The crown prince was late to realize that Sung Deok Im was the court lady sitting in front of him, and heard all the words he said.

The court lady couldn't hide the sadness on her face and went stone skipping to release her anger.

Yi San Receives Punishment After Being Falsely Accused by Princess Hwawan

Yi San started to face his enemies inside the palace. His aunt, Princess Hwawan, accused him of going out at night and engaging in fights. Due to this, King Yeongjo (Lee Deok Hwa) punished the crown prince for staying in his room for days.

Sung Deok Im then volunteered to accompany him and started reading the books Yi San bought for her.

The crown prince enjoyed hearing Deok Im's voice and it put him at ease during one of his darkest moments. He also apologized for the hurtful words he said during the ceremony.

Meanwhile, Princess Hwawan made another story about Yi San, which made the King angry. Without any words, King Yeongjo slapped the crown prince, which Sung Deok Im witnessed.

The King begged him to not be like his father. After breaking down, King Yeongjo left with a heavy heart towards Yi San.

Sung Deok Im Makes Promise to Yi San to Never Leave His Side

Sung Deok Im can feel the pain Yi San is going through. Even though it is forbidden, the court lady entered the crown prince's room and made a promise to protect him and stay by his side until he becomes the new King.

Yi San was stunned by Deok Im's pledge.

"The Red Sleeve Cuff" episode 5 attained a new impressive viewership rating of 10.2 percent, marking its highest record so far!

IN CASE YOU MISSED IT: 'The Red Sleeve Cuff' Episode 5 Spoiler: Is Lee Junho Ready to Level Up His Relationship with Lee Se Young?

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Shai Collins wrote this.