Dragon Tail.

3. Years

Natsu's POV

It hurts. IT F*CKING HURTS!

I'm never letting Gray get me pregnant again.

This. Is. Torture.

"You've got one out now Natsu. Just a bit more."

"Shut the f*ck up Acno!"

"There's no need to be rude. You've almost got the second one out."

.20 minutes later.

"Looks like they're triplets. Just one more big push and it'll be over. Ok."

"Ok." Ow, ow, ow.

.9 minutes later.

"Never again. Just no." Acno sounds incredibly tired. He's not the one who just gave birth to three babies.

"Do you have names for them?" Zeref-nii sounds so happy to be an Uncle. It's really really cute.

"The oldest is Kai, then Katsu and the youngest is Natalie. I think I'm gonna go to sleep now."

Acnologia's POV .(after the birth).

I never thought my past experience as a doctor would come into practice like this. No really. I just helped END give birth to triplets... What the hell has my immortal life become? I'm so confused.

.2 years later. (3rd person)

"Uncle Acno!"

Acnologia, the Black Dragon of the Apocalypse, looked at the three 2 year olds in front of him.

"What do you want brats?"

The youngest and only girl of the three, Natalie clung to his leg as she said, "Mama said it's food time."

Kai, the oldest of the triplets, added, "Uncle Zeref said to hurry up because otherwise Mama will eat all of it."

Acnologia snorted. Natsu would eat all of the food if he was ever allowed to.

Sitting down to eat, Natalie asked Natsu, "Mama, when are we gonna learn magic?"

"Yeah, we're old enough now aren't we?" Katsu agreed with his little sister.

Natsu smiled, Kai and Katsu looked just like mini versions of Gray. "Well I'm not going to be much help in teaching magic, I wouldn't even know where to start."

"I'll teach Natalie to be an Arcane Dragon Slayer then." Acnologia voluntered.

Zeref smiled, "I'll teach Kai and Katsu then. What magic do you two want to learn?"

Kai bounced out of his seat, "I wanna learn your magic Uncle Zeref!"

Katsu looked at his plate, "What magic did our father use?"

Natsu was surprised by the question, "Your father, Gray uses Ice magic." He answered.

Katsu looked determined, "Then I wanna learn Ice magic."

Zeref ruffled Katsu's hair, "I can do that. I won't be the best teacher for that as I have very little experience with ice magic, but I can teach you."

.4 years later.

"Try harder, Natalie. You won't be able to beat me at this rate."

"Got it Uncle Acno! Roar of the Arcane Dragon!" Natalie - looking much like a mini female Natsu - shouted releasing a powerful tornado of her Arcane Dragon Slayer magic. Acnologia took the blow head on, the force of it pushing him back a little over 100 meters.

"Good job Tally!" Was said in unison by Kai and Katsu.

Natalie smiled, "Thanks! Kai, Tsu!" 

Natsu's POV .(1 year later).

Acno and Zeref-nii have done a good job of teaching the kids to do magic, Natalie is now the arcane dragon slayer, Katsu is an ice mage like Gray and Kai is learning Zeref-nii's magic.

We made a new guild - Kai is the Guild Master. We've all got nicknames now after the sheer destruction we cause -- Zeref-nii is Black, Acno is Apocolypse, I'm Pheonix, Katsu's Cocytus - after a frozen lake of hell apparently - and Natalie is Calamity. Kai laughed when we realised we were just as infamous as Fairy Tail without once participating in the Grand Magic Games like them. Acno laughed even harder than Kai when he found out they were calling him Apocolypse - Acno is the Black Dragon of the Apocolypse after all.

"Kai, Katsu, Zeref, myself, Acnologia, Natalie. We are the Guild called Dragon Tail."

"Mama! Hurry up! It's food time now!"

"Ok! I'll be right there!"