Koibumi To 13-Sai No JoyuuKoibumi to 13-sai no Actress; 恋文と１３歳の女優; A Love Letter and a 13-Year-Old Actress; Lá thư tình và nữ diễn viên 13 tuổi; 情書與13歲女演員; 情书与13岁女演员; Una carta de amor y una actriz de 13 años

Fumi Isshiki works as an accountant at an entertainment agency. One day, he is transferred to the management department, where Ayano Haga, a 13-year-old child actress, seems to take a liking to him...? She is just a child, yet she acts more mature than most adults. A dramatic story woven between a professional child actress and her manager! (Source: Comic Fuz, translated)