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Castle J
Son Seongjun · 캐슬제이
Birthday
May 31, 1999
Zodiac
Gemini
Chinese Zodiac
Rabbit
Height
176 cm
Position
—
Nationality
South Korean
MBTI
ENTJ-T
Blood Type
O
Hometown
Seoul
Solo Debut
February 27, 2020
Fandom
Gem
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Introduction
Castle J, born Son Sung Jun, is a South Korean rapper and composer under TOP Media . In 2020, he made his official debut as the main rapper of the boy group MCND .
Schedule
🎂 Birthday in 207 days
D-207MCND — Devil Youth Club
Sep 10, 2026Fun Facts
- Castle J, BIC, Minjae, and Huijun learned dance in America in 2016.
- Castle J used to be a child actor.
- His hobbies are watching movies alone, eating alone, listening to music and shopping.
- His favorite foods are meat, sashimi, Coca Cola, and coffee.
- Castle J, Minjae and Huijun joined TOP Media in 2015.
- Castle J is a college student at Daegyeong University, majoring in K-Theater and Film.
- Castle J has been friends with IOI/Weki Meki's Yoojung for over 10 years.
- He remixed most of the tracks they danced to during their pre-debut days, such as "Dalla Dalla," "Kill This Love," and "Bad Guy."