Sseo-ni
써니 (original)
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 Italy.