Question: Which actress that was a member of South Korean girl group is co-staring in Unexpected Love?

full_context: Document 1: Seohyun: Seo Ju-hyun (born June 28, 1991), known professionally as Seohyun, is a South Korean singer and actress. She debuted as a member of girl group Girls' Generation (and later its subgroup TTS) in August 2007, who went on to be one of the best-selling artists in South Korea and one of South Korea's most popular girl groups worldwide. Apart from her group's activities, she has established herself as an actress, notably through her participation in the original and Korean versions of stage musicals including "Moon Embracing the Sun", "Gone with the Wind" and "Mamma Mia". She also starred in the drama "". She debuted as a solo artist with her debut mini album, "Don't Say No", on January 17, 2017, making her the third Girls' Generation member to debut as a solo artist.
Document 2: Jessica &amp; Krystal: Jessica & Krystal is an OnStyle variety TV show starring Korean American sisters Jessica Jung, former member of Girls' Generation and Krystal Jung of f(x).
Document 3: Baik (director): Baek Jong-yul (born 1970), known as Baik, is a South Korean film director. Baik worked as a visual artist and advertisement director before entering the film industry. His feature debut - a romantic comedy film "The Beauty Inside" (2015), deals with the love between a man who becomes a different person every day and a girl (played by Han Hyo-joo), who loves him. Baik said that there were definitely challenges to create a film with so many different actors playing the same character as each actor came to the set with his or her own interpretation of the character. His effort won him the Best New Director at the 52nd Grand Bell Awards in 2015.
Document 4: Because I Love You (2017 film): Because I Love You () is a 2017 South Korean fantasy-comedy omnibus film starring Cha Tae-hyun and Kim Yoo-jung. Directed by Joo Ji-hoong, it premiered on January 4, 2017. This movie starring Cha Tae-hyun is produced by his elder brother Cha Ji-hyun who also produced the film "The Grand Heist" starring Tae-hyun.
Document 5: Bae Suzy: Bae Su-ji (; born October 10, 1994), better known by the mononym Suzy, is a South Korean singer and actress. She is a member of the girl group miss A under JYP Entertainment .
Document 6: Love (2012 film): Love is a 2012 Taiwanese-Chinese romance film directed and co-written by Doze Niu. It stars Zhao Wei, Shu Qi, Mark Chao, Ethan Juan, Eddie Peng, Amber Kuo, Ivy Chen and Doze Niu. "Love" premiered in the Panorama section of the 62nd Berlin International Film Festival. The film features an ensemble cast, with the stories revealed to be interwoven as the plot progresses.
Document 7: Sweet Sixteen (2016 film): Sweet Sixteen (, literally combining the names of the main characters) is a 2016 Chinese-South Korean romance film directed by Jo Jin-kyu and starring Kris Wu, Han Geng, Joo Won and Lu Shan. It was released in China by Heng Ye Film Distribution on August 5, 2016.
Document 8: My New Sassy Girl: My New Sassy Girl () () is a 2016 South Korean-Chinese romantic comedy film directed by Joh Keun-shik, and starring Cha Tae-hyun and Victoria Song. This film, a sequel to "My Sassy Girl" (2001), was released in China on April 22, 2016 and released in South Korea on May 12, 2016.
Document 9: My Sassy Girl: My Sassy Girl (Korean: 엽기적인 그녀 ; literally, "That Bizarre Girl") is a 2001 South Korean romantic comedy film directed by Kwak Jae-yong, starring Jun Ji-hyun and Cha Tae-hyun.
Document 10: Unexpected Love (2017 film): Unexpected Love (also anown as: "Flying Kite" / "Bi Zui! Ai Ba" / "Biyeon") is an upcoming Chinese-South Korean romantic comedy film directed by Si-Heup Seong and starring Zhang Yixing and Krystal Jung.
Document 11: Krystal Reyes: Jolina Marie B. Reyes, better known by her screen name Krystal Reyes (born September 8, 1996 in Barangay Bulac, Santa Maria, Bulacan, Philippines), is a Filipino child actress who is currently a GMA Network contract artist.
Document 12: Krystal Jung: Chrystal Soo Jung (born October 24, 1994), better known by the mononym Krystal, is an American singer and actress based in South Korea. She debuted in 2009 as a member of South Korean girl group f(x) and has further participated in S.M. Entertainment's project group S.M. The Ballad. Aside from group activities, she has also participated in various television dramas such as "" (2011–12), "The Heirs" (2013), "My Lovely Girl" (2014), and "The Bride of Habaek" (2017).
Document 13: Your Wedding (film): Your Wedding () is an upcoming romantic drama South Korean film that depicts the 10-year love and friendship of two people from teenage to adulthood. It is written and directed by Lee Seok-geun and starring Park Bo-young and Kim Young-kwang. The film is scheduled to be released in 2018.
Document 14: Jessica Jung: Jessica Jung (born April 18, 1989), known professionally as Jessica, is an American singer, songwriter, actress, model, fashion designer, and businesswoman currently based in South Korea. Jung was born and raised in San Francisco, California. At the age of eleven, she was discovered by South Korean entertainment agency S.M. Entertainment and subsequently moved to South Korea. In 2007, Jung debuted as a member of the South Korean girl group Girls' Generation. The group later became one of the best-selling artists in South Korea, and one of South Korea's most popular girl groups nationwide and worldwide.
Document 15: Seohyun discography: Seohyun (born Seo Joo-hyun) is a South Korean singer, member of Girls' Generation and its subgroup Girls' Generation-TTS. Since debuting in 2007, she has collaborated with various artists and released several original soundtracks for South Korean TV series. Her career as a solo singer began in January 2017 with the release of her debut extended play "Don't Say No".
ground_truth: Krystal Jung