The unexpected lesson (Snape x reader)

The announcement

"I've told you a million times not to dress like this. And the next time I see you in this short skirt, I will make you wear a sack, I swear!" Draco spoke loudly to Y / N as they walked down the hall. She sighed in the exasperation. 

She was grateful for Draco acting like a big brother, even if he was one year older than her, but sometimes she needed the space. "I am not a little girl. I am 17. When will you stop acting like an old-fashion geriatric?!" Y / N turned to Draco and imitated an old-man with a cane. 

"You know what would be useful for you? Sex. Good long sex with a beautiful young lady." she hysterically started to laugh when she saw his face in shock of hearing the dirty word coming out her mouth. Draco was already embarrassed,

"It is unacceptable!" Snape's earth-shattering voice made the few students chatting in the hallway to panic, and they crowded the door on the way to their dining tables. 

Dumbledore seemed to be very absorbed in his thoughts while walking along with his colleague to the teachers' table. 

"Having sex in the 7th year is one thing, but now it seems that even the younger ones are only thinking of how to get ... shagged." his facial expression showed how much that thought caused him, and it made him even angrier the fact that Dumbledore was still lost in his deep thoughts. 

"We must not let this situation go out of control. I hope you heard about that stupid Ravenclaw girl getting pregnant, and even if I am ashamed, I must say I suspect that a Slytherin is also pregnant. Sir, with all due respect,

"Severus, hello!" the man lifted his eyes from the ground and looked genuinely surprised at Snape. "Did you follow me down the hall? Nevermind. Did you hear about those two pregnant girls?" Snape stopped walking and pinched the bridge of his nose, and deeply inhaled. "Yes, I did. What do you suggest we do?" he spoke with a deep low voice and sped up in trying to get faster to his seat.

"Severus, stay here. Your presence will be needed." the Headmaster returned to the crowd and held a very fatherly speech about the importance of sex education at such a young age. Most of the children were embarrassed, the others were laughing, and a few nerds did not bother to pay attention and continued to eat. Draco was covering Y / N's ears all this time "Shhhh, it's not for you. You won't have a boyfriend until you'll be in your 30s."

Snape's smirk grew bigger by watching how many children were already thinking about the consequences of sexual intercourse. Dumbledore, by the end of his now extremely long speech, introduced Severus as the new sex education teacher. 

Snape stood there, in disbelief, with the most shocking face he could pull out. "So, if you need pieces of advice on how to properly treat a man or a woman and how to protect yourself, please join professor Snape's classes. Have a lovely dinner!" and with a small gesture the tables were filled with lots of food, but it wasn't as if someone was hungry after such a marvel eulogy.