Sensei wa Kimusume ga Osuki

Koharu is a pure-hearted girl who comes to Issei's home to work as a housekeeper. Issei is a popular writer and womanizer who is pleased to learn that Koharu is a virgin. Moreover, his son is unkind to her and her feelings are always being toyed with by both of them. What will become of our Koharu? (Source: Shoujo Manga Maniac)