The protagonist of this play, an experience in the past caused her to lose confidence in herself.When she was a student, she was nicknamed “Sand” because of her rare name “Rain”, and was ridiculed, so she chose to keep a distance from others.The only person who smiled brightly at her was the sun.

In the process of getting along with Taiyang, Yu had a positive attitude towards life for the first time. After graduating from high school, he went to Tokyo to realize his dream of becoming a pastry chef.Although she didn't express her feelings to Taiyang when she left, for some reason, Yu had to return to Nagasaki. In her heart, she wanted to meet Taiyang again, but at the same time, she didn't want the other party to see her current self.