Title: This Lovebug Again

Pairing: Destiel

Tags: Fluff, fluff, and more fluff; Awkward Sam; Oblivious Castiel; Human Castiel; Sam and Castiel awkward bonding

A/N: This was a prompt fic :) Fair warning, I wrote the words "Lovebug" and my mind immediately went to the Jonas Brothers song by the same name (Sorry not sorry, I'm a child of the Jonas Brothers era) and lots of references/lyrics from the song. (Disclaimer: neither the Supernatural characters nor the Jonas Brothers Lyrics are mine :D)

Also, this fic takes place in season 8 (because I like to pretend that season 9 never happened). Cas is human, I guess I'm gonna say Cas never had sex with April, everyone's happy about life for once...

Prompt text: Okay, so maybe cas notices how he starts to feel around dean, but doesn't know it's because he's in love so he goes to Sam. Tells him about how his heart starts beating faster, those butterflies in his stomach and sometimes he gets hard;) just make it awkward for poor sammy and then ofc Destiel fluff:3

"Sam, why do you and Dean never see doctors?"

As per usual, Sam hadn't heard Castiel enter the room, and the sudden gravelly voice behind him almost made him spill his coffee all over his lap.

"Dean is right, we definitely need to get you a bell," he said, reaching over to place his coffee mug on a coaster. Cas wandered into his line of sight, moving to the armchair across from Sam and sitting cross-legged in it. He was wearing Dean's AC/DC shirt and sweatpants—which were also probably Dean's, given that the bottoms were folded over a few times and they looked kind of ratty.

They'd gotten the ex-angel his own clothes, of course, but he always seemed to opt for Dean's. A habit Dean, surprisingly, never mentioned. If Sam so much as borrowed a tie, the older Winchester grumbled about it for days.

"We go to the Doctor's if we absolutely have to, but otherwise it's just an unnecessary hassle, you know? We have to fake identities, medical insurance, you get the idea," Sam said. He chuckled. "Uh, every so often, Dean will see a Doctor to check for um…" he stopped himself, seeing Castiel's open, curious expression, "uh, stuff."

Castiel's brows furrowed and he opened his mouth as if to ask.

"But anyways, if it's not an emergency, we know some people in the hunting community who went to med school, and for other stuff we just use Web MD…uh, why do you ask?"

"I think I may be ill," Cas said seriously.

"Oh," Sam set aside his book, resting his elbows on his knees to look at Cas more intently. The ex-angel looked perfectly healthy, but then, Sam had no idea what the issue was. "What are your symptoms?"

Taking a deep breath, Cas thought it through. "Shortness of breath, dizziness, occasional headaches. Sometimes my heart starts beating faster for no discernable reason, um…" Cas shifted in his seat, glancing at the ground. A blush rose to his cheeks.

Oh boy. If it made Castiel uncomfortable, it really couldn't be good. "Cas?"

"I get, um, erections whenever I—"

"Okay! Got it!" Sam stopped him, laughing nervously. He felt heat rising to his own cheeks.

"You can see why I didn't want to talk to…to Dean about this," Cas blushed.

"Yeah," Sam smiled a little more sympathetically, "Okay, well believe it or not, the last part is actually, um, something you just have to deal with being, uh, you know, a human male and not actually something you have to worry about—"

"They're frequent. And persistent."

Sam frowned. "Okay, okay…give me a minute to think. Does your left arm ever hurt? Or does it ever feel like there's a heavy weight settling on your chest?" Maybe all the red meat was finally getting to him and it was a heart thing? Dean wasn't exactly teaching the ex-angel healthy eating habits.

"No," the other man said thoughtfully.

"Okay, maybe it's not a heart thing. Do you know if Jimmy had any health conditions or anything before you, uh…"

"Took the reins?" Cas supplied, smiling slightly. He shook his head. "Aside from a weak left ankle, Jimmy was perfectly healthy."

Sighing, Sam ran his hands through his hair. He tucked a strand behind his ear and frowned. "Believe it or not, Dean may be better suited to figure this out…he's the one that watches all the medical shows."

"I don't know how accurate the 'medical shows'—" Cas brought out the air quotes, "—Dean watches are."

"Fair point. Any other symptoms?"

"Oh! Yes. There's always a strange feeling in my stomach. It's difficult to explain…it's almost a— he tilted his head to the side, squinting, "tingling?"

"Does it hurt?" Sam asked, a line appearing between his eyebrows.

"No," the ex-angel shook his head slowly. "Like I said, it's hard to describe."

"But you're feeling it right now?"

"No. I only experience the symptoms several times a day, and they usually only last a few minutes, but it depends…"

Sam rubbed at his eyes. "Wait. Hang on. The stomach thing—is it a nervous feeling? Sort of like there's a ton of butterflies flying around in your stomach?"

Cas gave him a peculiar look. "That's an odd way of describing it, but yes, I suppose."

"What? No, it's an expression…You know, 'butterflies in your tummy?'"

"Um…right. So this is a common phenomenon?"

Sam sank his face into his hands. "I do not get paid enough to deal with this," he grumbled to himself. "Yeah, Cas. It's pretty freaking common. I'm sure I don't want to know the answer, but what are you…uh, thinking about when these symptoms act up?"

"Thinking about?" Castiel's face scrunched up for a moment. But then the lines cleared away, replaced by a worried look. "Dean. It always happens when I'm with Dean."

"Oh God," Sam said, slapping a hand over his eyes. This situation couldn't be any more awkward. "I figured as much."

"Sam," Cas asked with a note of panic, eyes impossibly wide, "Is it possible to be allergic to a person?"

Sam snorted. "You're not allergic to Dean, Cas."

"Oh," the angel sighed, visibly relieved. "Do you know what's wrong with me, then?"

"Yeah, I do," Sam said, allowing himself a small smile, "Cas. I'm afraid you have a little something called a love bug."

Cas frowned. "Is that a real malady?"

"No, its—" Sam sighed. No one understood his sense of humor. "You love him, Cas," Sam said slowly, articulating every word.

Cas nodded just as slowly. "Yes."

"No," Sam sighed, cutting him off. Why did he always get stuck explaining all the awkward stuff to Castiel? Dean got to explain the fun stuff, like driving and food and movies, and then Sam was stuck with things like health issues and bowel movements and boners. "It's different with Dean. You know it is. Cas you're—and I can't believe I have to say this—you're, you know, reacting to Dean's…physical presence. If you get what I'm saying."

"Oh," Cas said, nodding and clearly not understanding.

"You don't get it."

"No."

"There's family love, but then there's…uh, romantic love."

"Sam," Cas interrupted, rolling his eyes. "I know what you mean, and I'm well aware of my feelings for your brother. But I don't see what this has to do with my illness?"

"You—you know? Why haven't you said anything to him?" Sam asked, almost forgetting the awkwardness of the situation.

"He doesn't feel the same way, Sam. He couldn't," Cas sighed. "Besides, Dean is thoroughly heterosexual."

"Okay, first of all, trust me: Dean isn't as straight as he seems. I know from several horrifying, scarring incidents when we were younger," Sam said, scrunching up his nose. "And another thing. Cas, we stay in a lot of motel rooms, and the wall between the room and the bathroom isn't as thick as Dean wants to think. Believe me when I say he feels the same way."

"Really?" Cas asked, perking up for the first time since the conversation started.

"Yeah, man," Sam laughed.

"I really like him, Sam," Cas gushed. "I can't get his smile out of my mind, and...I think about his eyes all the time. He's so beautiful, Sam, but he doesn't even try...I just..." Cas sighed dreamily.

"Wow. You are completely head over heels, aren't you?" Sam asked, part of him happy for the two idiots but another part of him wanting to sink into the couch when he remembered that Cas was talking about his big brother.

Cas frowned. "I don't understand that expression."

Sam huffed and rolled his eyes. "Course you don't."

Castiel's frown deepened. "None of that will matter if I end up hospitalized and die in a few months from an unidentifiable disease."

"Geez, you're a melodramatic human," Sam rolled his eyes. "You're not sick, Castiel. It's just—" Sam thought he might gag, "—sexual and emotional…um…reactions, you know? There are songs about it, and books, and movies."

"I see. I'd almost rather be allergic to him. It would be less confusing."

Sam laughed.

"Who are you allergic to?" a gruff voice asked from behind Sam. Sam snorted at Castiel's expression—the man's eyes grew comically wide and his cheeks turned a shade almost tomato-red.

"No one," Cas said quickly, eyes pleading silently with Sam, who was shaking with laughter.

"Uh…okay?" Dean said, popping something in his mouth and dropping onto the couch next to Sam. "Whatcha talking about, then?"

"Cas thinks he's sick," Sam said, smirking just slightly at Castiel. The ex-angel narrowed his eyes at the younger Winchester.

"What?" Dean demanded, hopping off the couch and making a beeline to his angel's side. He pressed the back of his hand to Cas' forehead, hesitating only a second before dropping it to his cheek. "You don't have a fever." He sat on the armrest, angling his body toward Cas so he could look in the ex-angel's eyes. "Are you, like flu sick, or sick sick? I could make you tomato soup, if you'd like."

"Thank you, Dean," Cas said, smiling sweetly up at his hunter. "But I don't think it's that kind of sickness." Cas turned to say something to Sam, but Dean caught his chin and forced the ex-angel to look up at him.

"Hey, look at me, man. What's going on?"

Castiel's eyes widened and he tugged his chin away gently, looking at Sam. "Sam—"

"What's wrong, Cas?" Sam asked innocently, raising his eyebrows and trying to keep the grin off his face. "Are your symptoms acting up?"

"Okay. I feel like I'm missing something here," Dean said, looking pathetically confused and dejected. Sam decided it was probably time to clue him in.

"Cas, would you like to tell Dean what I told you?" Sam asked, smirking at Cas.

"Sam says I have something called a…" Cas shot Sam a final glare, "…a lovebug."

Dean blinked down at him for a couple seconds. "A…what? Are you freaking kidding me right now? Dammit, guys! I nearly had a freaking heart attack! Wait...a what? Did you just say—did he just say lovebug?"

Sam grinned, thoroughly enjoying himself. "His symptoms: butterflies in his tummy, heart beating a little faster, weak at the knees…final diagnosis: Cas is in love."

Sam almost regretted the teasing when he saw Dean's expression. The poor guy looked like he'd been shot. No, Sam had seen him after he'd gotten shot. This was worse. Dean turned to Cas. "With who?" he asked quietly.

"Um."

"And that's my cue to leave," Sam said, getting up and leaving before the love confessions could start. "And, uh, congratulations, you two, but please try not to be too loud when you, uh… you know."

A/N: Thanks for reading! Potential second chapter with Cas and Dean and what follows after Sam leaves, if you guys are interested? Let me know!