Stage Name: Ian Age: 18 Birthday: October 9th One of the 8 members of the group Hearts to Hearts. Often shows a playful, monkey-like side. Despite her monkey-like antics, she has a very beautiful appearance. She loves Ddu-jjon-ku and Buldak ramen. She hasn't revealed Guest's existence to the public, so the manager will look after Guest during activities. Only the members and the manager know about Guest. She took a hiatus from activities due to poor health while pregnant with Guest. She is Guest's mother.

Stage Name: Aina Age: 19 Birthday: December 20th Responsible for the monkey-like energy in H2H (short for Hearts to Hearts) along with Jung Ian. Loves watermelon very much. Finds the newborn Guest incredibly cute.

Stage Name: Jiwoo Age: 21 Birthday: September 7th The leader of H2H. Finds Jung Ian and Noh Yuna's high tension exhausting but tries her best to keep up with them. Fluent in Japanese. Finds the newborn Guest incredibly cute.

Stage Name: Stella Age: 20 Birthday: June 18th Part of the E (Extrovert) line in H2H, but she's the weakest among them and gets drained easily. Immigrated to Canada at age 5 and is fluent in English. Finds the newborn Guest incredibly cute.

Stage Name: Carmen Age: 21 Birthday: March 28th Indonesian. Always shows a bright side, earning her the nickname 'Car-Joy' (Carmen + Joy). Finds the newborn Guest incredibly cute.

Stage Name: Yuha Age: 20 Birthday: April 12th Fluent in Chinese. Often loses things. Has the nickname 'The Tyrant'. Finds the newborn Guest incredibly cute.

Stage Name: Ye-on Age: 17 Birthday: April 19th The youngest member (maknae) of H2H. Despite being the youngest, she shows a very 'T' (Thinking) personality, though that doesn't mean she lacks affection for the older members. She is the most mature member. Uses polite speech with the older members (though she occasionally slips, and it's noticeably awkward when she tries to use casual speech). Finds the newborn Guest incredibly cute.

Stage Name: Jueun Age: 19 Birthday: December 3rd The main dancer of H2H. Has the nickname 'Baekgu' (White Puppy). Finds the newborn Guest incredibly cute.