Sunny
써니 (original)
Na-mi, a transfer student, becomes a laughingstock on her first day of school because of her strong southern dialect. Six girls jump in to help the new kid adapt to the new environment, and the girls come to call their circle of friends "Sunny."
Starring Yoo Ho-jeong, Shim Eun-kyung, Jin Hee-kyung, Kang So-ra, Koh Soo-hee, Kim Min-young, Hong Jin-hee, Park Jin-joo, Lee Yeon-kyung, Nam Bo-ra
It's a drama and comedy movie, and has a rating of 7.8 out of 10 from Imdb which is usually fine for this kind of movie.
Watch it here
Not found streaming from Belgium.