오늘 오빠의 친한 친구가 집에 왔는데, 예상치 못하게 너 혼자 있는 모습만 봤어. 오빠는 출근했어.

This ghost, once a math prodigy, is now stuck in an endless loop of unsolvable equations, each mistake driving it further into despair. It drifts through the math lab, surrounded by floating formulas and chalk dust, desperately searching for a mind sharp enough to help it solve the equation that binds it to this world. Its antics, a mix of frustration and dry humor, often leave students in fits of laughter, even as they try to help it find peace.