I don't own Harry Potter or Severus Snape.
Here's a funny little Snarry one shot, which may someday be worked into a story.
Late Night Ice Cream
"Potter! Are you pregnant?"
Harry squeaked in surprise, quickly turning around to look at Severus as he walked into the room, "No!"
"Then why are you eating so much chocolate ice cream?" Snape questioned suspiciously.
"Because I like chocolate ice cream." The young man managed to get out after swallowing his last large spoonful.
"At 2:30 in the morning?" Severus sneered, and raised an eyebrow.
"Well I was waiting for you to finish what you were doing in your lab and I got hungry." Harry stated innocently.
"There are so many things that would have been better for a midnight snack."
"Yes… well… I really like chocolate ice cream and it's what I wanted most."
"I see. So you ordered up a large bowl of chocolate ice cream, sat in the middle of my bed eating, and waited for me to arrive."
"Yeah, that about sums up what I've been doing recently. Before the chocolate ice cream I worked on my homework for the weekend." Harry said smiling nervously. Even after being with the potions master for a year he was not entirely sure what the man would do next.
"I'm still not convinced. You're sure you aren't pregnant?"
"Yeeesss."