"Promise" (Cheating!Osomatsu x Reader)

Promise

{before i begin, reader relationship with karamatsu is completely platonic, meaning they dont like eachother romantically. please dont yet the wrong idea it ticks me off}

You walked along the river, concrete beneath your feet, and Karamatsu and Osomatsu with you. You held hands with Osomatsu, Karamatsu trailing behind you two. Your face had a bright smile. These two were your favorite. They helped you through your depressive episodes and were a shoulder to cry on. When Osomatsu asked you out, what else could you say than yes?

You sat at the Oden stand. Chibita greeted you two with a small nod, the bald man getting food for all three.

"Hey, (Y/N), you have work tomorrow, right?" Osomatsu said, grabbing a stick of oden.

"Mhm. I come home at... 10PM I think!" you say, chewing.

"10PM?! That's late! Are you sure you're not overworking yourself?!" Karamatsu exclaims worriedly.

You giggle and send Karamatsu a reassuring glance. "I'm fine, don't worry about it.

"A-Are you sure?" Osomatsu chimed in. "You only have one day off a week, like today!"

"I have to pay for oden somehow!" you say jokingly.

"I-I don't like it though." Karamatsu said. "You work in the Black Factory!"

"It's fine! It has good pay and comes with a place to stay!" you say taking a bit of food.

Osomatsu laughed and ruffled your hair. "Just make sure all the guys there know you're mine!" he says before pecking your cheek.

"Of course! I'd never leave you!"

"Promise?"

"Promise!"

...

You sigh and change out of your work uniform. Tomorrow was your day off, but you got off work early due to an accident. You decided to visit Osomatsu and surprise him with a gift.

It took a lot of persuading, but you were able to mooch a bit of extra cash from your boss to buy you and Osomatsu custom matching necklaces. It was the family crest in two halves. Each half making a necklace.

As you drove to the town, you couldn't help the uneasiness in your stomach. Something bad was bound to happen.

...

(haha nsfw)

Osomatsu let out a groan as he came into the condom, the girl beneath him letting out a moan as she felt the condom fill with warm cum.

"Let's take a short break, yeah?" Osomatsu says, squeezing the girls boob softly. She nodded, for her throat was sore.

"O-Osomatsu, a-are you sure you should so something like this?" Karamatsu said, covering his eyes as he poked his head through the door.

"Nah, it's fine! Come on, don't worry so much!" Osomatsu says laughing. "Come on Totoko-chan, round five!"

(bye nsfw lol)
...

You park your car outside the Matsuno Residence. The sun had set, pink and orange streams came from the horizon.

You knocked on the door, the gift tucked im a box in your pockets.

After a few moments, your eye caught a note on the window.

"Gone shopping! Let yourself in if you're (Y/N)! -Your Bestie, Kara" you read out loud.