B1A4's Sandeul is singing "You're Leaving Like the Season" for the 'Castaway Diva' OST.

The music video highlights the sweet friendship and romance between Seo Mok Ha (played by Park Eun Bin) and Kang Go Geol / Jung Ki Ho (Chae Jong Hyeop). "You're Leaving Like the Season" is an emotional ballad about someone leaving your side after having meaningful moments together.

Listen to Sandeul's "You're Leaving Like the Season" above! Have you been keeping up with 'Castaway Diva'?