Yves is part of Up unit ("tall girl unit"), whereas Chuu is part of Line unit.
When they were both in the dance academy, they were in separate buildings. Yves was in Urban Dance, Chuu was in hip hop.
Both have low self confidence and have debut with little training time with the company, but Chuu is on the Positivity Line, Yves is a pessimist.
Yves dislikes being affectionate and doing cute aegyo, but Chuu likes both and dislikes being called sexy.
Yves is good at Yoga, Aerial Yoga and Pilates. Chuu isn't on any of them.
On the other hand: Chuu was an anchor leg (Ace) on school relay teams, Yves wasn't. On Chuu Can Do It, Chuu managed to close the distance on Yves, but with the gap being too great from the beginning of the six-legged 6x200m relay, Chuu couldn't lead the comeback.
Chuuves is often called "입추" (Ibchu) by Korean fans. 입추 also referred to a period of the year -- 立秋, the 13th solar term (out of 24) on the traditional East Asian calendars. 입추 signifies the beginning of autumn in East Asian cultures; it starts on the 7th-8th August. Thus, some fans decided the 8th August is "Chuuves Day"/"YvesChuu Day"
Yves' strengths according to Chuu: "Yves unnie's strength is that while she might not seem like it, she is very witty and humorous. And she doesn't lack anything on the performance side. I keep a very close eye on her. (Laughing) My score for her is 100/100."
Yves' weaknesses according to Chuu: "And her downside. She gets up late"
Yves: "Chuu, you always talk kindly, very energetic, and has a powerful voice. Whenever I feel down, you keep me busy."
Chuu [laughing]:"Like, chaotic?"
Yves: "Yes chaotic. But thank you for keeping me busy!"
Chuu [being disturbed by a bug]: "Oh, a bug!"
Yves: "Am I a bug to you?"
Around midnight, on Yves' 22th birthday (in 2019), Chuu made her cry by imitating a cockroach. Then when midnight struck, the other members came to the practice room to sing her "Happy Birthday" with a cake.
Yves met her at a dance academy, before joining BlockBerryCreative. Chuu was sitting very quietly in a cap. Yves thought Chuu was a quiet and shy person, and that she could befriend her because of that. She stopped her in a elevator to ask for her number. They became friends and ended up starring in a web drama together (a cameo) as a part time job.
Chuu's first impression of Yves
Chuu: "[Yves] looked friendly but was somewhat cold. [Yves denied that statement] She was cold... [Addressing Yves] You were smiling brightly. So I wanted to get closer to her. And I talked to her and she was somewhat cold...So I thought "maybe I was wrong"...But she talked back to me. I could feel she was a very nice person."
Since Yves was the one who approached Chuu first, she denied this statement.
Chuu picked Yves as the member whose image changed the most from the first time she met her:
Chuu: "Yves unnie seemed very shy at first, but now she's the comedian and boss unnie :) "
They had to part and pretend not to know each other since Yves was revealed before Chuu.