Lee Yoo Young has opened up about her close friendship with Goblin actress Kim Go Eun. The two attended the Korea National University of Arts together.

The actress of OCN's time-travel drama Tunnel talked about the Goblin star during an interview, to commemorate the conclusion of her hit drama. Lee Yoo Young revealed, as cited by Soompi, "Kim Go Eun debuted before I did, so she's a senior to me in terms of acting. That's why I receive a lot of advice from her. Before I started filming for 'Tunnel,' she told me that it's crucial to stay alert while filming a drama. She also taught me how to adapt to the environment on set."

Both the actresses have started off with different characters and they often told each other that they would try to play each other's roles.

Lee Yoo Young also stated that Kim Go Eun watched her drama, praised and encouraged her.

Yoo Young confessed, "I didn't think I looked very pretty in the first few episodes of the drama, so I told her that I came out really ugly, and she responded, 'What are you talking about? You are so pretty. Your character is great and your acting is amazing.' She gave me a lot of strength."

Tunnel wrapped up with a record-breaking viewership ratings. The finale episode that aired on May 21 gathered average viewership ratings of 6.5 percent and peaked at 7.1 percent. The drama scored average ratings of 7.2 percent and peaked at 8.1 percent with its target audience which is between the ages of 25 and 49, Soompi reported.