This chapter is a response to the prompt I got in a message:

One day Klaine have the house (Blaine's, Kurt's it doesn't matter) for themselves and decide to take an advantage of it. And during the most amazing sex of their lives Blaine pulls a muscle in his back. You can write this or if you are not comfortable with this theme you can skip to the morning after. Blaine obviously has pain and difficulty walk straight but of course, he is Blaine so he insists on going to school. And during the day he must repeatedly explain to different Glee members how it happens. Everytime he tried to brush it off as a strained back from dancing but Kurt always snortes or just laughs. Finally they are in the choir room and maybe Santana or Puck is making fun of his Warbles step-and-slide moves and that they don't get how he could hurt himself like that (because they of course figured it out that it is from sex) and Blaine just snaps and yelled it while Kurt is laughning because he find it incredibly funny.

I included that because I feel like it would seem pretty vague without the explanation. This is different than most of the stuff I write, so it's probably a little rough. But here you go!

Blaine winced as he lifted up his arm to shut his locker door. Despite taking four Tylenol pills before school, it had done nothing to help his soreness. His arms felt like jelly, but it was mostly his back. He wasn't just sore, he had pulled something, and he had pulled it good. He wasn't sure how he would ever make it through dance rehearsal in glee club.

"Hey!" Kurt said cheerily, coming up behind him. Blaine slowly turned around and smiled at him.

"Hey," he said, trying to appear normal. "Did you sleep good last night?" Kurt nodded and offered to walk him to class. Blaine went with him, even though it hurt more with every step.

"What's the matter with you?" Kurt asked him, looking concerned. "Did I do something?"

"I'm fine," Blaine told him. "Just sore. Really sore. It's my back, mostly." Kurt frowned.

"I'm sorry," he said, as if it was his fault.

"Don't worry," Blaine assured him. "I'll be fine. Let's go to calculus." Since Blaine had taken some advanced classes at Dalton, he was taking a senior math at McKinley with Kurt, Mercedes, and Rachel.

"You're walking funny, Anderson," Mercedes commented as they walked into the room. Blaine felt his cheeks grow hot.

"I pulled a muscle in rehearsal yesterday," he said a little too quickly. Kurt snickered next to him, and Blaine elbowed him hard in the side. That got him to shut up. Mercedes looked at him funny and then shook her head.

"I find it funny," Kurt whispered to him.

"I find it painful," Blaine argued, and sat down.

Class was fine, since Blaine didn't have to do much moving around. He made up an excuse for everyone who asked him why he was walking funny. He said everything from dancing to helping his dad put Christmas lights up. Hopefully no one would figure out the real reason he was sore.

Things were fine until glee rehearsal. Blaine walked in to find Kurt, Puck, and Santana already in there.

"Hey," Blaine said to him, and sat down slowly. He'd taken more Tylenol with no luck in feeling any better.

"Hummel told us the real reason you've been waddling around here like a duck," Santana said casually. Blaine froze. He looked over at Kurt. His boyfriend blushed and sank down in his seat.

"She blackmailed me," Kurt said in his defense. "Don't ask."

"The two gay twins lost their virginity to each other," Santana said- loudly. "I guess Blaine really is too small for Kurt. He can't escape without a hurt back."

Kurt was laughing at that point, but Blaine snapped. "I pulled a muscle," he told her through gritted teeth. "Get over it." Everyone but Blaine was laughing at that point. He just sank into his seat, cheeks red and hot with embarrassment.

Author's Notes:

Talk about awkward!