"One for all. All for one"

Jeongmin, Riyeon, Zico, and Eunji were bestfriends for God know how long. The four grew up together, playing together, and even went to the same high school. They have nothing to hide, they have nothing to keep a secret. They never separated, and cannot be separated. But when love starts to bloom between them,

can they still remain as ‘besfriend’ ?