Chapter 7: Some Feel the Heat

Disclaimer: Song lyrics from Robert Palmer because I can't help myself. Isayama owns Attack on Titan.

Warning: Okay here's the Eruren smut you've all been anxiously waiting for.


Eren was curled into a ball on the couch, with Erwin patting his back. "I'm sorry your owner is a coward." He murmured. The dog shifter whined in response, shaking and sweating. "I know it's not the same, but I'm willing to offer myself as a substitute, if you don't mind." The dog's ears perked up. "After all, we always end up cuddling in the morning when I spend the night." Erwin smiled, watching Eren uncurl and stare up at him with wide eyes.

"You…" Eren began, unsure. "You'll participate in Heat with me?"

"Yes, if you're comfortable with that." Eren nodded vigorously. Erwin chuckled, stroking Eren's hair and leaning in. "Just let me know what you like and anything you prefer not to do."

"I…haven't really…it's my first Heat." Eren whispered timidly.

"Oh?" Erwin grinned, remembering all the times Hanji rambled on about shifters and Heat. He was glad for once that he paid attention. The dog shifter blushed, hiding his face. Erwin smiled, lifting Eren's chin with a finger. "Hey, don't worry. I'll take care of you."

He could feel the hot skin on his fingertip, and saw Eren's eyes glazed over as the Heat overtook him. The dog whined as Erwin's fingers slid down his neck, lightly teasing his collarbone. He leaned forward, brushing his lips against skin, and Eren shuddered. He quickly picked Eren up and carried him to the bedroom before things got too far.

Laying the dog down, Erwin opened a bedside drawer and took out the necessary accessories for sex: lube and condoms. Eren was squirming on the sheets, clothes sticking to sweaty skin. Erwin put his knee on the bed and bent down, lifting Eren's shirt over the dog's head, who shuddered again at the cool air. His nipples were already tightening, goose bumps scattered on his skin.

Erwin undressed swiftly, watching Eren closely. He wanted to take this slow, be gentle, but he could already tell the Heat was too strong and they would end up getting rough. Plus, he wasn't sure how dominant Eren would be during the process. The way Hanji explained it, Heat could make a dog submissive or dominant, depending on the partner, the dog's preferences, how much control they had, and other environmental factors.

He figured he would test the boundaries first, get his feet wet before jumping in. Eren wasn't in complete control of himself at the moment, so Erwin had to be careful not to frighten or take advantage of him in this state.

The dog was tugging at his pants, trying to pull them off. Erwin helped, and Eren sighed in relief. The blond leaned down further, positioning himself over Eren, keeping his legs on either side of the shifter's hips.

"Eren, are you ready?" he asked softly. The dog merely whined again, reaching for him. Erwin kissed him on the lips, tentative at first, but Eren pushed them closer, opening his mouth and biting Erwin's lip. He was caught off-guard for a moment, then took control of the kiss.

Eren writhed beneath him, clawing at his back. Erwin felt slick skin rubbing against his own with the shifter's every movement. He wrapped an arm around Eren, holding him, and the dog arched, nearly bending in half to make their bodies meet. Erwin made a sound deep in his throat that Eren responded to immediately with one of his own.

A challenge for dominance.

Erwin looked him in the eye, and Eren didn't back down. The color changed to yellow, and he seemed like a different person—powerful, intimidating, and ferocious. This must have been the side of Eren who attacked those Military Police thugs and fought the wilds who attacked him. Erwin wasn't a pushover, however. He was used to being on top and in control. Rolling his hips to make his point, he leaned in to bite Eren on the neck.

The dog howled, kicking and flailing. Clearly it was a sensitive area. Erwin didn't want to hurt him, so he let go and licked the area for reassurance. Eren bared his teeth and struck forward, biting Erwin back.

"Hey!" the deep, commanding voice subdued the dog only slightly, who held on with both teeth and limbs, wrapping himself around Erwin tightly. The Commander wouldn't give up, however. He wrestled Eren until he was pinned to the bed. "Easy. We're doing this my way for now." He told the dog, who narrowed his eyes but began to relax.

Erwin smiled. "That's better." He murmured, kissing Eren's neck and listening to the keens and moans the action elicited. He spread the dog's legs, dipping his fingers into the lube and coating them. Gently, he poked at Eren's hole, testing for resistance. The dog yipped out of surprise and arousal. Erwin pressed his thumb against the whole, pushing, and Eren arched again, claws digging into his shoulder.

"Shhhhh, relax now." Erwin whispered in his ear, and he felt the shifter submit. One finger edged inside, slowly, carefully. The dog let out a long, high-pitched whine. The finger curled, poking at the walls inside, letting Eren adjust. He placed soft kisses along his collarbone, jawline, and cheek.

The dog nuzzled his neck, encouraging him to go further, lightly nipping anywhere he could reach. Erwin slid another finger in, keeping it close to the first and feeling Eren tighten around him. The dog squirmed, eyes squeezed shut. After a moment Erwin moved his fingers apart, scissoring. The shifter jerked, eyes opening with a gasp, neck bared. Erwin went for it, kissing and sucking on it as his fingers moved inside Eren, drawing out moans and squeaks.

He inserted another finger, quicker with Eren's desperate panting and clawing. The shifter's legs clenched around him, trying to draw him in further, hands still gripping Erwin's shoulder and back. Eren started biting again and Erwin flexed his fingers, spreading them as wide as they could go. The dog made sounds he never heard from a human's throat before, writhing again.

It was so hot, he was sweating and could practically see the steam rising from their bodies. Eren was a furnace, Erwin's fingers burning. He took a deep breath before aligning himself. Eren relaxed when he felt the tip of Erwin's cock press against his hole, rubbing the rim. He howled again when it entered him. Erwin groaned at the scalding heat that sent a jolt through his body, forehead pressed into Eren's neck, eyes closed and lips parted as he breathed out.

He moved slowly at first, going in a little and pulling out, feeling Eren pulsate around him. He was bigger than three of his fingers, but the shifter demanded more. His legs were wrapped around Erwin's hips, squeezing, pushing him in farther. Erwin went in more each time, making the dog feel like he was being teased when really he just didn't want to hurt him. Soon neither of them could handle the agonizing pace and sped up.

Erwin knew when he hit Eren's prostrate when he started barking wildly, howling and keening with frantic limbs. His hand shot down to his own dick, squeezing it, but Erwin pushed the hand away. "Now, now, no need for that." His own hand took over, surrounding Eren's cock and pumping in time with his thrusts.

The dog thrashed, licking at his jaw, cheek, neck, shoulder. Erwin found the right angle and kept ramming in, hoping his neighbors couldn't hear the yowling created by each thrust. Eren's legs were moved onto his shoulders, where they hung limply, thighs occasionally spasming and twitching.

At the height of his climax, Erwin gave a throaty yell, while Eren practically screamed. It was the most human sound he made all night, taking Erwin by surprise, but afterward his tongue was lolling out of his mouth while his eyes held a dazed and utterly satisfied expression. Erwin smirked down at him, pulling out slowly and collapsing beside him on the bed. They lay there, chests heaving, bodies tingling, for a few minutes.

"Feeling better?" Erwin asked, turning onto his side to examine the shifter's condition. Eren didn't speak, instead he turned lazily, still panting. His arms had fallen around his head, and Erwin could see blood beneath his fingernails, feeling the sting of his scratches. "I didn't hurt you, did I?"

Eren flopped over onto his side, facing Erwin, arms curling up against his chest. His eyes drifted closed, expression calm. Erwin watched him fall asleep and brushed some hair out of his eyes.


If Erwin thought it would only take one good fuck to end Eren's Heat, he was mistaken. A few minutes into the dog's bath after he woke up, Eren was trying to mount him. He practically dragged the taller man into the tub with him, flipped them, and began rutting.

"Hey, what are you doing?" Erwin scolded. "I'm trying to get you clean. Are you saying you want more?"

Eren answered him with a kiss that involved more teeth than tongue. He was more aggressive, and Erwin had a feeling he wouldn't back down this time. Water splashed onto the tile floor of his bathroom. Erwin tried to push Eren off, but the dog was surprisingly strong in his state.

He received a growl for his efforts, low and warning. When Erwin narrowed his eyes and tried to pry Eren's hands off his arms, the dog bared his fangs and made a more vicious sound, snarling. Every time Erwin tried to take control, to push Eren away or attempt to switch their positions, Eren tightened his grip and snarled threateningly.

"No need to be so mean, if you want to go again we can, but you have to let me." Erwin said in a calm, soothing voice.

Eren barked at him, as if disagreeing with something he said. His face was determined, stern, not angry but dangerous. He wanted to top this time. Erwin frowned, preferring to give rather than receive, but there was no arguing with a dog in Heat.

The shifter didn't bother with lube, probably not thinking about its benefits even though Erwin tried to explain that the reason why he was trying to get out of the tub was to get the bottle and condoms.

"I'm coming back, I just need to get some things. Eren!" the dog wouldn't let him leave, clinging and growling. "You're being difficult." The shifter made a low whine, barking. Erwin sighed and laid back against the tub. Eren leaned forward and latched onto Erwin's collarbone, taking skin between his teeth and biting down hard. Erwin hissed, gripping the sides of the tub until his knuckles turned white.

The shifter didn't prep him or anything, just lined himself up and shoved in, moving recklessly. Erwin clenched his teeth to keep from yelling. He told himself this was to help the dog who would probably be an apologetic mess when this was all over, if he even remembered what happened. He was doing this to help Levi, who was too afraid to handle it on his own. Thinking of it that way, Erwin was glad this was him instead of his boyfriend. No matter how strong Levi was, he wouldn't fair well with this rough pace without getting worked up to it. At least that's what Erwin thought, and he was glad his boyfriend wasn't forced into this with no other choice than to comply.

Erwin moved, trying to keep up with the wild thrusting and biting. His hands slipped against the tub's walls, spine bumping up against the tub roughly. He slipped further down, water lapping around his chest, forcing Eren to change angles and lean further over him. When he reached for Erwin's cock, the man made a noise and shoved him away.

"No, you'll yank it off at the rate you're going." Erwin told him sternly. Eren looked offended, angry, reaching again like a petulant child. Erwin used his knee to hold Eren back, who barked and tried to get around him, making whining noises. "I understand you want to help, but you don't really know what you're doing."

The shifter made a low sound again, almost demanding, and pointed instead, giving up on fulfilling the act himself. Erwin glanced down at his throbbing cock, hyperaware of Eren's dick shoved halfway up his ass. Cautiously, he gripped the base and stroked himself as Eren watched. The shifter looked pleased, continuing his thrusting and getting deeper each time. Erwin threw his head back, letting it hang over the end of the tub. Eyes closed, he didn't think, just let himself feel. It was awkward at first—he rarely masturbated, there was hardly any need—but soon he allowed himself to relax and enjoy the sensations.

Eren was still going at a breakneck pace, but he was hitting the right spots and making Erwin gasp and moan, even crying out a few times. It was the most noise he made during sex in a while. This time when he rode out his orgasm, he felt Eren licking cum leaking from his tip. The bulk landed in the water over his stomach. When the dog pulled out, he fell back against the other side of the tub, breathing heavily.

Erwin felt dirtier than when they came into the tub, considering all the bodily fluids floating around him.

"I think…a shower…might be better." he panted. Eren's head flopped forward, and after a moment lifted so he could look at Erwin. "Can you shower by yourself?" Erwin asked. He didn't want to get fucked against the bathroom wall if Eren felt so inclined to go for round three while they were trying to get washed up again. The shifter nodded, but made no move. "You go first…when you can."

Erwin was actually feeling pretty tired, but he didn't want to go to bed covered in sweat and cum. He lifted the stopper and let the water drain, rinsing the tub before getting out. Leaning against the counter, he dragged a towel across his skin to dry himself off. Eren moved slowly, lifting himself to a standing position. Wobbling slightly, he turned the showerhead on and let the spray wash over his body. It seemed to invigorate him. Soon he was scrubbing his hair with shampoo. Erwin trudged into his room to get them both a clean set of pajamas. He had a feeling they would be sleeping for a while.

When he returned to the bathroom, towel wrapped around his waist, Eren was getting out. The dog yipped happily at him, tail wagging and ears perking up. It was odd, feeling the furry appendage tickling and slapping him during sex. Erwin handed the shifter his clothes and stepped under the water, which Eren left on, waiting for him. The dog dried off and stepped into the pajamas, stretching and yawning widely.

Erwin let the cold water trickle down his body, bracing himself against the wall. He was slightly dizzy from exertion, his legs still trembling from the relentless pounding he received, and in turn gave earlier. Absently, he wondered if Eren was tired as well, or if the Heat gave him extra stamina and energy to deal with the emotions and physical activity he was forced into.

After a while he started actually cleaning himself, rubbing shampoo into his scalp and lathering soap over his body. His lower region was still sensitive, making him jump when he swiped the soapy rag between his legs. Shaking his head at the absurd situation he landed himself in, he washed himself off and stepped out of the shower, looking for a dry towel to use. Eren's was discarded on the floor.

He heard a low, deep "woof" and whirled to see Eren watching him, eyes yellow and piercing.

"Ohhhh no. Not again." Erwin warned, shaking his head. "We both need some rest."

The dog said nothing, instead offered a clean, dry towel. When Erwin reached for it, Eren pulled it back. Erwin frowned at him, stepping forward to tug on the towel. He saw something flash in Eren's eyes as the dog tugged back.

"Stop that. Now." Erwin commanded, yanking the towel out of the shifter's hands. He received a guilty whine and watched the dog warily as he dried off. Half-turning to his clothes on the counter, he started putting them on. The towel was flung over the top of the shower rail.

The dog was on the bed now, still watching, laying outstretched in the middle. Erwin sighed as he plopped down onto his stomach, only getting his pajama pants on before giving up on dressing himself. He felt Eren's eyes on him.

"Get some sleep, Eren." Erwin told him.

The dog matched his position, head turned to face him. His tail wagged lazily, the swish of air sending a breeze across Erwin's back.

He drifted to sleep with Eren still staring at him, eyes shifting from yellow to green.


Author's Note: This took longer than I thought it would for some reason, and not exactly how I originally planned but meh. Will there be more Heat sex? Who knows, not me. Feel free to suggest any ideas for this AU~