Kissing/Sex/Homosexuality
Anne mentions that she has many male admirers at school. Anne has heard rumors that a boy in her neighborhood, Sallie, has already had sex with someone. Anne says that several of the boys in her class have filthy minds, but she does not give examples of their behavior.
The adults are angry when they learn that Peter has read a book intended for adults only. Anne never says if the book has any sexual content, but she refers to the book as forbidden fruit.
Mrs. van Daan wears tight dresses and pats and touches Mr. Frank to flirt with him. Mr. Frank does not respond.
Everyone in the Secret Annex teases Anne for lying down on the same bed as Mr. van Daan, but Anne is quick to say in her diary that she would never want to sleep with Mr. van Daan in the way they were suggesting.
Anne reads a book called Eva's Youth by Nico van Suchtelen, which contains mentions of prostitutes. The book also mentions menstruation, which causes Anne to long for her own menstrual cycle to start so that she can be a "true" adult. Anne discovers white smears in her underwear. Her mother says this indicates that her period will start soon. Anne wishes she could use sanitary napkins, but they are no longer available for purchase, and she says that her mother's tampons are not intended for women to use until after they have had a baby. Later, when Anne reads her own early writings, she is embarrassed by her open discussion of such indelicate subjects.
Mr. Dussel is said to have lived with a Christian woman, and their sexual relationship is implied.
Anne is supposed to write new words she learns, and she makes note of brothel and coquette but does not define them.
When Anne enters puberty, she is somewhat self-conscious about the changes in her body, but she is also proud of becoming a woman and says that her monthly period is like a sweet secret. Anne says she has the urge to touch her own breasts. Anne has had discussions about sex with her father, who has told her that she is too young to understand physical desire, but when Anne has romantic dreams about a boy named Peter Schiff, she believes that she understands adult desires well.
Anne writes about spending the night with her female friend Jacque and being curious about her friend's body, which she had never seen. Jacque refuses Anne's request that they seal their friendship by touching each other's breasts, but she allows Anne to kiss her. Anne says that she feels ecstatic when she sees nude female drawings in art books.
Anne says that sex has only been a topic she has heard discussed in hushed and horrified tones. Anne's mother once told her never to discuss sex with boys, and Anne wishes her mother would give her a more thorough explanation of the facts of life.
In January of 1944, Anne and Peter van Daan begin a friendship tinged with romantic desires. Anne dreams of kissing Peter. By April, Peter and Anne sit with their arms around each other, and Peter kisses Anne's cheek. They kiss each other's cheeks several more times before kissing on the lips in May 1944. They spend time alone every evening and always kiss goodnight.
Mrs. van Daan says she has never explained sex or reproduction to Peter, and she assumes that her husband has not. Neither parent knows where Peter has obtained any knowledge of sex. Anne has learned a few details about human reproduction from a sex education book.
Peter shows Anne that his cat Boche is a male by pointing out the cat's sexual organ. Anne knows the Dutch word for vagina, but neither she nor Peter is sure of the word for penis. Peter says he plans to ask his parents to tell him the word for the male sexual organ.
Anne says that loving someone in the romantic sense will eventually include physical love. She says that if two people are really in love, they do not have to be married so long as they are committed to each other for life. Anne believes that purity before marriage is a silly concept and says that it wouldn't be a problem for a man to enter a marriage with some previous sexual experience.
Peter is more knowledgeable about sex than Anne is, and she asks him many questions about sex, although she doesn't discuss his answers in detail. Anne wonders if Peter actually knows how female genitals look because the way he talks makes it seem like he still lacks some key knowledge of the female form. Anne writes about how she used to think that urine flowed from a woman's clitoris and how her mother feigned ignorance when Anne asked her about what her clitoris was. Anne writes a detailed description of female genitals in her diary, describing how their outward appearance changes while standing and while sitting. Later, Anne describes female genitals to Peter who is surprised to learn the details.