Song Ji-oh

From teen years to adulthood, two friends linked by warmth and tension grow apart — until one is asked to accompany the other through her final days.

Chu Sang U, a strict computer science student, clashes with design major Jang Jae Yeong after removing his name from a project, leading to unexpected sparks.

Here's Park Jae Chan in his youth. The spring day of his life has finally come. While being unable to fully enjoy the spring due to growing attention from the public and his hectic schedule, he gets a friendly letter from a stranger called “Winter”. By doing what Winter tells him through the letter, he finally learns how to truly enjoy spring.