Shiraishi (白石) is a former Sankai High student, who passed away and became a spirit.
He was in love with classmate Hazuki Okita since Middle School, although they never made eye contact. In their first high school year at Sankai High, he tried to show his feelings to her, by writing a giant message in the ground of schoolyard using lime. He sent her a message on her cell phone, asking her to come see the schoolyard from the rooftop on Wednesday at 6am, so his giant message wouldn’t be ruined by students when they come to school, and he tried to write the message during the night before, but he didn’t have enough lime and could only write “好” which means “Love” although it can also be seen as “女子” meaning “Girl”, so he went to buy more lime, but ended falling from his bike on the way back to his death. His spirit lingered, hoping to show his message to Hazuki, so he sent her the same message on her cell phone the following year at the same period, but he still couldn’t compose his message and she didn’t make it on time as she doesn't usually wake up early. He tried again another year, which caused Hazuki to seek Rinne, who provides him enough lime to compose his message, but as he learns that she got a boyfriend since her first high school year, he decides to pass on and asks to remove the message.