Sakura no Uta: The Tear Flows Because of Tenderness.

Kusanagi Naoya lost his mother at a young age. As his father was a painter who traveled across the world, the only person who could help Naoya cope with the loss was his friend, Misakura Rin. Unfortunately, she moved away while they were in elementary school. Now in high school, the colder, steeled Naoya deals with the death of his father. When things look like they will turn for the worse for Naoya who already has trouble opening up to people, a new transfer student comes to his class...

(Source: MU)