お隣の天使様にいつの間にか駄目人間にされていた件

Amane Fujimiya lives alone in a messy apartment. His next-door neighbor Mahiru Shiina is admired at school for her beauty, grades, and composed image. A rainy-day encounter brings the two into closer contact. Mahiru starts spending more time helping Amane put his daily life in order. Both deny romantic intent, but their relationship slowly moves beyond ordinary friendship.