Body swap

Zenitsu and (Y/n) are put in a mission together at (mountain name) to destroy a different kind of demon.

"Your gonna protect me right
(Y/n)-chan?" Zenitsu cried

"Z-zenitsu-kun, you have to stand on your own if you want the girls to marry you" (Y/n) said at him

"B-but (Y/n)-chan!"

"Come on we're already here" (Y/n) said and they walked in, (Y/n) then used her Byakugan and looked around to find the demon.

"Ara~ what do we have here?~" they turned to the owner of the voice and saw a lady with a horn and wings sitting at the tree branch

"Who are you?" (Y/n) asked in seriousness ready to take out her sword out same with Zenitsu who is still shaking but still in high alert

"Hm~ oh! How rude of me~ I'm Nicca~" she introduced at them and jumped down from the tree branch.

"Now, why don't you entertain me~" the demon smirked and dashed towards (Y/n), the demon was about to claw her but Zenitsu immediately snatched (Y/n)

"W-wait! We are not tasty food, okay! So please don't eat us!!!!" Zenitsu yelled while being chased around.

"Just stay still dammit!!" The demon said while chasing and clawing Zenitsu who continued to bodge.

While the demon is being distracted, (Y/n) made one clone and switch with it, so the clone is now in Zenitsu's arms while the real (Y/n) silently unsheathed her sword and dashed towards the demon girl.

"Flame breathing; first form: Unknowing fire"

(Y/n) then slashed the demon girl's neck from behind and the demon girl's head rolled to the ground while (Y/n) clone disappeared in a puff of smoke which startled Zenitsu but then calmed down when he saw (Y/n) unharmed, when they were about to walk away they heard the demon girl speak.

"How unfair, I didn't have much fun! Oh well, I guess I will have to give you a goodbye gift" After she finished her sentence she released a dark purple smoke and she then turned into dust.

When (Y/n) and Zenitsu inhaled the smoke they suddenly feel sleepy and they then collapsed onto the ground.

(Next morning)

"Ahhhh!!!!!!" (Y/n) woke up because of the screaming but the voice seems familiar, she then stood up and saw her yellow hair fall at her eyes 'wait- yellow hair!?!?!'

"Who!? Who are you!? Why are you look like me!?!?" (Y/n) immediately turn around and her eyes widened at what she saw 'why does that girl looks like me!?!?! Wait a minute, that's it! It's because of that smoke that we inhaled from the demon! So that means...'

"Z-zenitsu-kun?" (Y/n) asked

"(Y/n)-chan?" Zenitsu also asked "ehhh!?!?!? So that means you're in my body and I'm in your body!!" He said and (Y/n) nodded

"W-we have to find a way to switch back" (Y/n) said and begin to think

"How do the girls always carry this? It's so heavy" (Y/n) heard Zenitsu said, (Y/n) got curious at what is it so she looked at Zenitsu but then turned deeply red when she saw Zenitsu copping her chest.

"Z-ZENITSU!!!!!!" (Y/n) shouted and kicked her own body in embarrassment.

(Time skip)

~at the butterfly estate~

Shinobu's POV:

I was checking if Tanjiro and Inosuke's injuries are healed but then I heard Zenitsu's familiar shout.

"S-SHINOBU!!!!!" Zenitsu (or you) shouted and kicked the door out of it's place.

My eyes widened and so is Tanjiro and Inosuke, since when did Zenitsu got this strong. But then I blinked when Zenitsu (or you) launched himself (herself) at me and hugged me while crying, I was about to throw him (her) away but then he (she) spoke.

"S-shinobu-chan!.... Wahh!!..... Help me! *Sniff*..... *Sniff*" Zenitsu (or you) said still crying on my shoulder.

I was annoyed by his (her) crying 'I was about to go to (Y/n)-chan's house and invite her for tea after I finished with my work' but then (Y/n) (or Zenitsu) came in in a hurry and tripped at nothing, she (he) then fall face first.

But the next thing surprised us.

"(Y/n)-chan! I gotta go to the bathroom!" She (he) said

"What!?!?" Zenitsu (or you) shouted

"You heard me! I gotta go to the bathroom!" (Y/n) ( or Zenitsu) repeated loudly

"You can't!" Zenitsu (or you) said while forming his (her) hands an x and shaking his (her) head.

'why would Zenitsu not let (Y/n)-chan go to the bathroom?' I thought but then my eyes widened along with Tanjiro and Inosuke who also noticed it 'did (Y/n)-chan/(mispronounced name) just call Zenitsu/monitsu
(Y/n)/(mispronounced name)?'

3rd POV:

Zenitsu (or (Y/n)) and (Y/n) (or Zenitsu) keep yelling at each other, which resulted to all of the Hashiras to check if there is something wrong.

"What the f*** is going on here!?!?!" Sanemi shouted angrily, which resulted for (Y/n) (or Zenitsu) to get frightened and cling to Zenitsu
(or (Y/n)) for dear life.

They then saw (Y/n) (or Zenitsu) clinging to Zenitsu (or (Y/n)) like there is no tommorow.

"(Y/n)-chan! Why are you clinging to Zenitsu!?" Mitsuri exclaimed, Obanai then got (Y/n) (or Zenitsu) off Zenitsu (or (Y/n)) and the Hashiras except Shinobu shielded her (him) from him (her).

"W-wait! Y-you g-got i-it a-all wrong!" Zenitsu (or (Y/n)) exclaimed and waved his (her) hands in front of her face when Sanemi walked towards him (her) and ready to punch the living out of him (her).

"W-wait!" Shinobu said and shielded Zenitsu (or (Y/n)) along with Tanjiro and Inosuke.

"Out of the way!" Sanemi exclaimed trying to get to Zenitsu (or (Y/n)) but they wouldn't bodge an inch which pisses him off.

Obanai, Tengen, and Rengoku decided to help Sanemi and they succeed to get Shinobu, Inosuke, and Tanjiro to get out of their way by pushing them aside and hold them in place.

Sanemi then walked towards Zenitsu (or (Y/n)) while cracking his knuckles.

Zenitsu (or (Y/n)) who had nowhere to run to walked backwards with tears threatening to come out.

't-they....they didn't believe me except Shinobu-chan, Tanjiro, and Inosuke-kun....but I t-think I have an idea...b-but please..' Zenitsu (or (Y/n)) thought "PLEASE WORK!!!" Zenitsu (or (Y/n)) shouted which startled everyone.

Zenitsu (or (Y/n)) then mumbled an incantation while putting his (her) palms together and then parted it slowly when it started glowing and then appeared a two bottles of identical potion.

(Just imagine that there's two and it's so tiny)

'I-I did it!'

"Zenitsu! Catch! And drink it!" Zenitsu (or (Y/n)) exclaimed and (Y/n) (or Zenitsu) immediately catch and drink it without hesitation and so did Zenitsu (or (Y/n)).

The two then started glowing brightly and it blinded everyone so they covered their eyes from the brightness.

When it died down they saw (Y/n) in Zenitsu's place who is nearly in tears and Zenitsu in (Y/n)'s place.

And let's just say that (Y/n) didn't talk at all of them in the pass couple of weeks except for Shinobu, Tanjiro, Zenitsu, and Inosuke, much for their delight.

Even though they apologies to her many times.

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