Disclaimer: Supernatural and all of its characters belong to Erik Kripke and the CW Network.
This is how I hope the writers go about Castiel falling if/when that occurs. I really hope that it's not just a passing, "oh, btw, Cas fell, no big deal" situation.
"I didn't have to die to go to Heaven,
I just had to go home.
Into the arms of my angel,
Into the peace I left behind.
All I had to do to save my own life
Was to look into your eyes."
-"Heaven" 3 Doors Down
If you were to ask him today, Castiel could tell you the exact moment that he fell. He had been sitting in the middle of a field with the Winchesters, his back pressed against the cool glass of the Impala's windshield. He had been watching Dean's outstretched arm, pointing out constellations (which Cas had been positive that Dean and Sam had made up, because he knew every constellation in the sky and he was pretty sure that 'Staracus' wasn't one of them) when he'd been snatched into the sky.
"Castiel." His father's voice was booming and echoed through out the white room. He spun in a tight circle, his brow furrowed in confusion.
"Father? Is that you?"
"Of course, Castiel. We need to talk." Cas tucked his hands into the pockets of the trenchcoat.
"I thought you were dead." He whispered, his voice shaking.
"I'm God, you imbecile. I can make people think whatever I wish. That's irrelevant. What I want to talk about is you, Castiel."
"Me?"
"Yes, you. You've disobeyed Heaven, my son. You've rebelled against us at every turn since you met those boys. There must be consequences." Cas' blood began to boil in his veins.
"Was it not you that told us to love humans as we love you? I love you, Father, very much so. Therefore, I must love the humans more."
"We both know that your feelings for Dean Winchester surpass that, don't we?" Cas was silent, his gaze falling to his feet. "Exactly. You've risked everything, and put the entire Garrison in danger on several occasions for the sake of those boys. You've fallen in every other way imaginable since returning from the pit. You must be punished."
The hands that closed around the bases of Castiel's wings were large, and he couldn't see them, but he could feel the ripple of tendons underneath warm skin as the gripped tightly. He flinched, his eyes squeezing shut and his blunt nails digging half-moon cuts into his palms.
When his hands and knees his the wet, muddy grass of the field, the sound of his wings tearing from his back echoed over the concerned voices of the boys calling to him. The scream that tore form his throat wasn't something that he could classify on the decible scale. Dean was beside him, pulling the trenchcoat off his shoulders and lifting his chin.
"Cas? What the hell is going on?" He asked, his voice low. Cas gritted his teeth and pressed his forehead into the grass in front of him.
"F-falling." He ground out, his jaw cracking from the force of grinding his teeth.
"Falling?" Dean whispered, his hand falling to Cas' back. He gasped quietly and Cas turned his head to look at him. Dark blood stained the ivory skin of Dean's fingers. He could feel it soaking through the fabric of Jimmy Novak's dress shirt, and he knew. His wings were gone. His grace had been torn out of his vessel through the gaping wounds over his shoulder blades. His fingers tightened on the strands of grass in front of him, dirt finding its way underneath his fingernails as he tore the grass from the Earth with another feral scream.
"Dean," He whimpered, tears streaming off the end of his nose. He felt Dean's arm slip around his torso, pulling him closer, but the pain still tore through his body. "Dean, it hurts." He cried. "Make it stop. Please." Dean's own voice was shaky with emotion when he responded.
"How? Cas, you gotta tell me what to do here...I don't know how to help you if you don't tell me." Cas shook his head slowly. He'd tell Dean how to help if he had any semblance of an idea himself. He dropped forward into the grass, rolling until his back was pressed to the grass.
The cool air that hit his gasping chest when Dean tore his shirt open and pushed it off his shoulders made him shudder violently. Dean's fingers pressed against his shoulders, trying to roll him back onto his stomach, but he swatted them away. The damp grass felt good against his burning skin.
"D-Dean, I'm sorry." He choked out, fighting off a wave of dizziness as his fingers closed around Dean's wrist. Dean looked down at him through misted green eyes and shook his head.
"What are you sorry for, Cas? This isn't your fault." He sniffled, drawing his free hand over his nose like a child. Cas smiled up at him weakly.
"For everything, Dean." A violent cough wracked his body before his head fell limp against the grass.
"Cas?" Dean called out, shuffling closer and gathering Cas into his arms. He pressed his forehead to the soft fluff of Cas' shaggy, dark hair and let the tears flow from his eyes. Ragged sobs shook his body as his tears soaked into Cas' hair. He raked his fingers through the strands at the base of Cas' neck. "Cas? Buddy, c'mon...I need you, Cas. Don't do this to me." He whispered, brushing his lips over Cas' temple. Sam's hand fell on his shoulder carefully.
"Dean," He whispered. Dean shook his hand away violently.
"He's going to be fine, Sammy." He snarled, his eyes squeezed shut as more tears burned behind his eyelids. "Cas, please." He whispered. It was then that he felt Cas' fingers weakly gripping the front of his shirt.
"Dean." He whimpered, his voice quiet and shaky. Dean pulled away, his eyes flying open as a laugh that bordered on being more of a sob broke from his throat. He brushed his thumb over Cas' cheekbone and tilted the other man's face up to look in his eyes. Behind him, Sam let out a sigh of relief of his own.
"You're okay." He whispered, a shaky smile fitting itself to his face. Cas nodded slowly, his hand moving to Dean's shoulder.
"I think so." He shifted and winced. "Still hurts, but...it's not as bad anymore."
"What the hell happened up there?" Dean questioned. Cas stared at him for a long moment.
"I was punished. My Father, he was...upset with me for all the ways that I had rebelled against Heaven since," He swallowed and looked away briefly. "Since I pulled you out of the pit..."
"I...you falling is my fault?" Dean questioned, his brow furrowing.
"No, it's not your fault, Dean. My Father simply wanted to punish me. For falling in love with my charge, because it made you my priority and not Heaven. You've always been my priority, Dean." Dean gave him a soft smile.
"You love me, Cas?" Castiel's head tilted to the side minutely.
"Of course I love you, Dean. How could you not see that?" Dean smirked and leaned in, brushing his nose over Cas' gently. Cas pulled his head back slightly, confused. "What...what are you doing?" Dean chuckled and hooked his hand behind Cas' neck.
"Just remember what you learned from the Pizza Man." He laughed, pressing his lips against Cas' solidly. He waited until he felt Cas' tongue pressing against his lips before deepening the kiss. He groaned low in his throat when Cas' fingers tangled their way into his hair.
Somewhere behind them, Sam cleared his throat uncomfortably and they pulled apart. Dean smiled down at Cas for a moment.
"I thought you had died, you know. I was worried." He whispered. Cas frowned at him and brushed his hand over Dean's cheek.
"I'm sorry to have worried you, Dean."
"It's okay, Cas. You're still here. How are you still here, by the way?" Cas laughed softly and struggled to his feet, Dean and Sam's hands on his biceps helping him to stay upright. He glanced over at Dean as the boys shuffled him into the back seat of the Impala, mindful of the wounds on his back. Dean frowned as he surveyed them. They would need stitches.
"It's simple." Cas breathed, wincing when his back was covered with Dean's jacket. He smiled at the boys fondly and leaned back against the seat gingerly. "I came home."