Question: What nationality is both Kang Seul-gi and Red Velvet?

Context paragraphs:
Kang Seul-gi: Kang Seul-gi (born February 10, 1994), better known by the mononym Seulgi, is a South Korean singer.  She is a member of South Korean girl group Red Velvet.

Red Velvet discography: The discography of the South Korean girl group Red Velvet consists of one studio album, five extended plays, and twelve singles. Red Velvet was formed by the Korean entertainment company S.M. Entertainment in 2014, and consists of five members.

Red Velvet (band): Red Velvet (Hangul: 레드벨벳) is a South Korean girl group formed by S.M. Entertainment.  The group debuted on August 1, 2014, with their digital single "Happiness" and with four members: Irene, Seulgi, Wendy and Joy.  In March 2015, Red Velvet added a fifth member, Yeri, to the group.

Dasymutilla occidentalis: Dasymutilla occidentalis (red velvet ant or eastern velvet ant), is a species of parasitoid wasp native to the eastern United States.  It is commonly mistaken for a member of the true ant family, as the female is wingless.  The species ranges from Connecticut to Missouri in the north and Florida to Texas in the south.  Other common names include cow ant and cow killer.

Cake Man Raven: Raven Patrick De'Sean Dennis III (born 1967), better known by the alias Cake Man Raven, is an American baker and owner of the Cake Man Raven confectionery bakery formerly of Fort Greene, and now of East New York, Brooklyn.  DNAinfo.com called him "the foremost red velvet baker in America," and the "New York Daily News" wrote that he "turned Dixieland dessert red velvet cake into a Brooklyn thing."

Al Moses Manerson: Al Moses Manerson is an artist manager, songwriter and producer who specializes in A&R, promotions, marketing, sales and production.  He is president and CEO of Red Velvet Entertainment, a Los Angeles and Atlanta-based boutique management and consulting company.  Prior to joining Red Velvet in 2003, Manerson was general manager of Real Deal Entertainment, senior vice president of marketing and promotions for Platinum Records, national director of retail for Columbia Records and Northeast regional gospel promoter for A&M Records.

Velvet Book: The Velvet Book (Бархатная книга) was an official register of genealogies of Russia's most illustrious families.  The book is bound in red velvet, hence the name.  It was compiled during the regency of Sophia (1682–1687) after Tsar Fyodor III of Russia abolished the old system of ranks ("mestnichestvo") and all the ancient pedigree books had been burnt to prevent contention between the feuding aristocratic clans.

Winter Garden (S.M. Entertainment): Winter Garden is a special winter project by S.M. Entertainment which includes three Christmas singles from their female artists, BoA, f(x) and Red Velvet.  The three singles were released on different dates, with f(x) releasing the first song on December 15, Red Velvet on December 18, and BoA on December 22.

Red velvet cake: Red Velvet cake is traditionally a red, red-brown, or "mahogany" colored layer cake, layered with white cream cheese icing or Ermine frosting (sometimes called "cooked roux" frosting).  It has a distinctive fluffy texture owing to the gas-producing reaction of alkaline buttermilk with acidic vinegar and/or acidic non-alkalized cocoa.  The cake is commonly served on Christmas or Valentine's Day.  Common modern red velvet cake is made with red dye, however the red color was originally due to non-Dutched anthocyanin-rich cocoa.

The Velvet: The Velvet is the second mini album by South Korean girl group Red Velvet.  It was released on March 17, 2016, by S.M. Entertainment.

Supporting paragraphs: Red Velvet (band) Kang Seul-gi
Answer: South Korean