Under The Sea (KiriBaku Mermaid AU)

-15- Drowning

"Baku... No reject?" He asked looking hopeful.

"No. I didn't Kiri." Bakugou responded bushing his thumb on Kirishima's cheek.

"B-Bu-" Bakugou cut him off.

"Everything I said I didn't mean." He pressed their foreheads together and rested them with a small smile.

"I didn't mean it alright?" Kirishima gave a subtle nod.

"That is a... nice human?" The child whispered Shinsou who gave a apathetic nod.

"Yes, there are many nice humans. We hang around them." He explained Midoriya nodding along. Kirishima pulled his head away from Bakugou's and wrapped his hand around his waist, his fingertips overlapping.

"Baku has such small waist." Kirishima chuckled to himself making Bakugou blush.

"It's not that small." He mumbled back quietly, just a bit embarrassed. Suddenly Kirishima pulled him closer so their chests were pressed together, he arched his back so he could get a proper view of Kirishima. The mer's heavy breaths fanning out on his face.

"Baku..." He spoke under his hot breaths, pulling Bakugou impossibly closer into him.

"Can't take it anymore~" He purred looking Bakugou's body over, Shinsou seemed to have noticed what was happening so he willed himself over his fear and pushed himself forward, Kirishima was immediately on alert, grabbing Bakugou and using his tail to cover the two of them, he let out a deep predatory growl shaking Shinsou to his core but he knew he needed to solve the issue.

"Kirishima. Either give me Bakugou or finish the process." Kirishima snarled at Shinsou's proposition.

"My Omega will not leave my arms." He growled clutching Bakugou closer.

"Wha- Whats wrong with him?..." The child asked, Midoriya turned to the kid and wrapped an arm around his shoulder, pulling him closer for comfort and safety.

"The stress from thinking he was rejected caused Kirishima to go into rut. Its what happens to Alpha's when they meet their mates. He isn't thinking right and he might hurt the human." The child gulped before looking Kirishima in his eyes accidentally, big mistake. Fear riddled his body from the intimidation in the Alpha's eyes, he instantly started crying, pushing his face into Midoriya's chest and clinging onto him.

"Shinsou, I'm taking the kid back to everyone." Midoriya spoke before leaving, Bakugou still couldn't understand what was going on.

"Bakugou, Kirishima went into rut. You need to either get away from him or get him to do what needs to be done. Whatever you do, don't let him fill out his needs." He spoke clearly knowing Kirishima wasn't in the right state of mind to listen. Bakugou tried to squirm and look Kirishima in the eyes but he was met with a tight squeeze to his hips and a dark growl. Bakugou tried again, this time being successful. He looked Kirishima in his eyes, fear filled him as he gulped from the predatory look he was getting from the Alpha.

"Kiri..." He whispered taking Kirishima's face in his hand gently.

"Kiri, you need to do it now, I know you said you didn't want to but I want you to... Ok?" Kirishima huffed before shaking his head. "Please Kirishima. Please do it for me. I want this I promise. I want this!" He shouted starting to tear up. Kirishima growled in conflict with himself, he was going past his natural instincts and hurting the only thing he held dear in his heart, he slowly moved towards the water, the rational part of his brain taking over for a second. He gently laid Bakugou in the water, holding him up for just enough time to let out a single sentence.

"Kiri sorry, Kiri loves Baku..." He then pushed him under the water his Alpha screaming at him and trying to fight but he held Bakugou under the water not moving a muscle. Bakugou didn't struggle, nor did he worry, he trusted Kirishima. Panic set in after he took in his first breath of air, but he refused to let it overpower him, the same as Kirishima was doing. He slowly closed his eyes excepting his fate. He knew he would be with Kirishima properly soon anyways. The blackness took over his vision as he felt it all fade away, the last thing he could recall before it all ended was him being pulled out of the water and hearing Kirishima's pain-filled weeps.

-Perspective Change-

Kirishima pulled Bakugou out of the water, tears streaming down his face as inhumanly sad sounds left his mouth, whimpers and calls to his cold Omega. He let his head drop, pulling Bakugou's body into his own, holding him close hopping he would magically wake up. His heart was throbbing and his Alpha cried out before screaming at him. He laid Bakugou on the sand, waiting for things to happen but nothing did, he looked to Shinsou worriedly.

"Its not working. Why isn't it working." He growled getting angrier by the second. After a few seconds of harsh glares and mental death threats a cough was heard from under Kirishima before a gasp broke the silence. They both looked to Bakugou who was now breathing, Kirishima frowned.

"Did I not finish it properly?" He asked the purple-tailed mer who shrugged, he brought Bakugou back to the water to try again but when he was submerged Bakugou was breathing perfectly. He pulled Bakugou out of the water and checked over his body grinning as he figured out it worked.

"Baku!" He trilled being relieved he was alive. Within a few seconds of laboured breath Bakugou opened his eyes with a smile.

"Kiri... It worked..." He whispered as he looked over his body.

"Wheres my... tail?" He asked in a low voice his throat hurting from the events they partook in earlier.

"It will come slowly, it's going to be painful but at least it doesn't all come in one go." Shinsou answered since Kirishima was too happy to speak, he was slapping his tail on the hand and trilling like crazy. Like a gun shot all those sexual urges flooded back since he instinct to care for Bakugou was depleting. He spun his head back and growled at Shinsou who took that as his que to leave, he dived into the water leaving Bakugou and Kirishima alone. Kirishima growled before lifting Bakugou onto his tail letting his legs wrap around it.

"We use legs while Baku has?~" He asked gripping his thigh harshly.

"Kiri... My head really hurts..." He mumbled but Kirishima didn't like that answer, he growled. "Kiri I'm serious my head really hurt, and I feel like I'm going to puke." All of the sudden he slapped his hand over his mouth, shooting his eyes open before leaping off Kirishima's tail to throw up on the sand beside them.

"Stomach does not like human food." Kirishima growled going over and rubbing Bakugou's back soothingly.

"It only gets worse from here." He chuckled after wiping his mouth. Kirishima's hand slid from his back down to the rim of his swim trunks, his finger breaching the elastic and sliding along the edge.

"Baku please, I begging, can't take it longer..." He panted using his hands to grab Bakugou by his waist and pull him so they were pressed together.

"Kirishima, I don't feel good." He tried to explain but Kirishima continued to plead.

"Please Baku it hurt." He whined dragging one hand up and grabbing Bakugou's peck and the other travelled to his nether region, stopping when he felt the first few scales start to breach his skin, he ran his fingers over the small bumps grinning.

"Baku is getting scales~"