When sufficient time has passed, Severus collects the papers to mark them and compare handwriting further. This will certainly tell him more about each of these students and he puts them securely into his warded scroll case. He is glad to see that even in the new Hogwarts there are some students who care about study, learning and marks.
"The next portion of the class will be safety, hygiene and health, assuming there were no further questions of structure and function." He looks around the room. There had been almost no questions on these matters - on the actual content of the course. Either the booklet had been impenetrable or exceedingly clear.
The body is a complex system. Cleanliness is important to prevent the spread of DISEASE!" Severus speaks this word sharply to get the attention of the students who have begun to talk among themselves.
"It is important to be clean in all sexual matters, lest one spread disease from one person to another, or from one part of one's body to another. There are different bacteria and noxious substances that should not be transferred between one's penis, vagina, mouth or anus." These words are spoken easily with no inflection. He had practiced. "And one should always wash one's hands and any objects employed, especially if they will be entering another person. I hope I don't need to tell you to keep your genitals clean."
He points at his diagrams as he speaks. "It is particularly important not to insert an organ, or an object, even a finger into one orifice and then another without washing it thoroughly in between. If anyone has any questions regarding specific activities you may ask me now, or you may come at any time I am available in the Hospital Wing."