Tropical Memories ~Natsuiro no Symphony~

Hero is high school 3rd grade student. He can't talk with girls because of shyness and uneasiness feeling. He likes popular girl Erika. It is rumored that she prefers sportsmen. Because of that hero is going to train mind and body during the summer in order to confess to the lady of his heart. He knows that Erika spends the summer at elite Pao Pao resort. It's impossible to get there without prior reservation, so hero applies for a part-time job on the island. And so summer begins.

[From vndbreview]