Human Kacchan and Mermaid Deku au (cw male pregnancy/birth, mommy Deku)where they meet after Katsuki gets tangled in seaweed (or some cliché bs like that) while swimming in the ocean and mer Deku saves him. The two of them end up being infatuated with each other and while it’s

intense, their relationship is only physical, no matter how much Deku might of wished it otherwise.

But he doesn’t say anything, just takes what Kacchan has to offer because he’s not dumb enough to think that a /human/ would ever want anything with a merperson.

When the two of them are apart that truth is harder for Deku to bear but every night when they meet in the secluded cove they’d claimed as their own Deku thinks all of the heartache is worth it.

Katsuki’s warm firm hands smooth away his worry, his scorching hot mouth chases away the ache in his heart, & his eyes, his gorgeous, fire filled eyes, stare at Deku as if he’s his entire universe.

It’s all enough to keep Deku coming back again and again. And without fail Katsuki is there waiting for him every night as well

But eventually Deku feels his body slowly begin to change. His belly grows larger and his small chest begins to fill out. It’s soon obvious to not only

him but to Katsuki as well.

Deku is pregnant.

The anger and surprise that flashes across Katsuki’s face is evident and in that moment Deku makes a choice- he flees.

Back into the depths of the ocean where Katsuki can’t follow. He swims away as fast as he can go, heedless of

furious sound of Kacchan’s voice screaming at him to come back.

But he can’t go back. The anger in Katsuki’s eyes had scared him and it didn’t matter if his heart broke at the thought of not seeing his Kacchan anymore because the baby growing inside of him meant more to him

than anything and he’d protect it at any cost.

So Deku stays away as the baby inside of him grows stronger and bigger everyday. Despite his loneliness, he’s happy. Motherhood had been something he’d longed for his entire life and every kick and flutter he feels inside of him

fills his heart with joy.

But his thoughts would often still inevitably drift to Kacchan. He missed his touch, his voice, the feeling of wholeness that came from being with him.

He knew the thoughts were pointless. He’d been nothing but a fuck for the the human and truthfully

Deku couldn’t blame him for being upset about a baby coming from their trysts. Hell, Deku hadn’t even known breeding with a human was even possible!

But despite how much his heart hurt whenever he thought of Kacchan, Deku would always end up with a small smile on his face,

his webbed hands placed protectively around his growing tummy because his baby was half Kacchan’s and Deku would now, in a way, always have a part the man he so desperately loved with him.

When the day of the birthing finally came, Deku swam to an underwater cave he had found

weeks ago that he had deemed safe enough to hunker down in. It was a difficult birth and Deku more than once wished that he wasn’t alone for it. When the baby was finally out, the relief Deku felt was short lived as he quickly realized it was more human than mer.

In place of a tail fin it had two chubby little legs and there were no gills in sight. Even in his weakened, panicked state Deku knew he had to get it to the surface and as he scooped it up in his arms he said a silent prayer of thanks that the cave he’d picked wasn’t very deep.

As he broke the surface of the ocean, the babe in his arms immediately started screaming and Deku thought he’d never heard a sound so beautiful in all his life. He cradled the baby high against his chest, trying his best to protect it from the waves that lapped against them. He

was exhausted & trembling but he knew above anything he needed to find land immediately. He was still trailing blood & it wouldn’t take predators long to find him and his little one.

He headed towards a small island he knew was near by. It seemed to take forever as he fought to

swim while still holding his screaming baby’s head above water. Eventually he spotted the shore and he let the waves help carry them to land.

For a long while, he just lay on the warm sand, hugging his little one as he sobbed in relief. His body shook from a combination of

exhaustion, blood loss, pain and relief.

But his baby was okay, was alive, and that was what mattered above all else.

When his tears began to abate he sat up as best as he could and stared down reverently at the small baby in his arms. Gently he brought a hand to it’s head and

smoothed down the wispy blonde hair that was already frizzing as it dried in the salty air. The only tells that the baby was anything but human were a few patches of scales that dotted the skin along its hips, ankles & shoulders and a few tiny rogue ones along its chubby cheeks.

Based on what little knowledge Deku had of human anatomy, he guessed that it was a little girl.

He smiled, tears running down his cheeks once more, as he settled on a name for his daughter, his dream come true.

“I love you, my little Yumeka,” he whispered to her as he shifted

her so that she could nurse from his chest. I love you more than the sun or the moon or the entire ocean and I’m going to take care of you no matter what it takes.”

-tbc-