* Fanfic based on a fanart by Sgrimp on Twitter.

* I couldn't think of a better title; If you know one, please feel free to tell me. ^^

* Default name "Yuki" and gender-neutral pronouns are used.

Sometime after Satan's pact with Yuki, he had locked himself in his room and only comes out to eat. He also doesn't answer their questions and soon they just assumed it's his usual thing. Though one day, he was holed up in the library.

"You know, is it me or Satan's kinda being Levi right now?" Mammon asked while busily browsing Akuzon. Everyone else but Lucifer, Yuki, and Satan is in the common room right now.

"You can't compare Levi's nerdy lifestyle to that, Mammon" Asmodeus replied. "But it is a little concerning. Maybe he might have some feelings of regret for making a pact with Yuki. I think."

"Speakin' of which, where is Yuki?"

"Yuki's in their bedroom since this morning. I don't really care what they do in there." Leviathan said, he's playing a game and his eyes were glued to his D.D.D.

"Oh I know! Big brother Mammon will check up on Satan!"

"Mammon, did you hear yourself just now?" Asmodeus retorted.

"Hey, I'm still your big bro!" Mammon grimaced. "And if you're thinkin' I have some ulterior motive, I ain't got one!"

"Creepy," Leviathan said. "Ahh… Great you just made me lose focus."

"We're all going to check up on Satan, let's go!" Asmodeus marched towards the door. "That means you too, Levi."

"Ehh… Pass."

"Beel? Belphie?" Asmodeus turned his attention to them.

"I'm staying here with Belphie, Asmo. Look how peaceful he's sleeping on my lap right now."

"Sooner or later you're gonna get hungry and wake him up just to grab a bite, Beel," Mammon replied.

"Mm… We're coming too then…" Belphegor said as he slowly lifted himself up Beelzebub's lap with a yawn.

The five brothers went to Satan's room, but he wasn't inside, so they went to the library next. There, Satan has a pile of books at his sides with peculiar titles. They haven't noticed yet, but Satan's ahoge was moving like a metronome. He hasn't noticed them entering until Mammon picked up a nearest book from Satan.

"Let's see what our brother's been reading… "An Idiot's Guide to Understanding Humans"? What the heck is this…?"

"This one looks interesting… "69 Ways to Seduce Humans". Wow, I think I'd like to read this one," said Asmodeus with an intrigued look on his face.

Leviathan peered in on the cover of the book Satan was holding, "101 Ways to Romance a Human."

"Gaah…!? What are you all doing here!? Ah—ouch…!" Satan was so surprised that he fell off his chair.

Asmodeus' lips curled into a mischievous grin, "Oh~? What's our little baby brother doing trying to read guides to interacting with humans? Let big brother Asmo teach you the art of seduction!"

"Uh, he's supposed to be the 4th brother," said Belphegor.

"But if not for our powers, we're actually the older ones. So, I'm the big brother!" Asmodeus said proudly.

"Hm… Good point," Belphegor replied.

"All of you…" Satan sighed as he stood up, "You're all disturbing me."

"Now don't be shy! I'm in a good mood today," Asmodeus insisted, and he had already grasped Satan's face to nudge him cheek-to-cheek.

"This is getting embarrassing…" said Satan and for some reason his ahoge was waving side-to-side.

Mammon was the first to notice, "Hahaha! What's Satan's hair doing!? It's wagging like a dog's tail!"

"LMAO This is a discovery!" Leviathan pulled out his D.D.D. to record.

"He's more like a cat though. Ooh, maybe we can think of it as his cat ears!" said Asmodeus while playing with Satan's side hair.

"Cut it out, Asmo…or you're going to get it…"

"Aww, is our Satan shy? Was my love that pleasant?"

"Stop it…" This time, Satan's ahoge was drooping.

"This is gold! Who knew we can tell what Satan feels just by looking at his ahoge!" Leviathan was too busy enjoying the fun, "Quick, someone call Yuki over here!"

Speak of the devil, Yuki and Lucifer had just arrived. They were from different places and saw that everyone else was gathered in the library.

"What's all this commotion about?" Lucifer said with furrowed eyebrows. "I could hear your loud voices from the entrance hall."

"Ack! Lucifer's back!" Mammon shrieked. "Wait! You gotta check this out! Satan's hair is moving on its own!"

"Like an anime character!" Leviathan grinned.

"…I suppose that's surprising to know," said Lucifer.

"That's so cute!" Yuki said with sparkling eyes.

The moment Satan saw Yuki with their excited eyes, his ahoge curled into a heart shape. Satan realized it and quickly covered his head with his hands. He thought no one would notice this unique trait of his so he wasn't sensitive about it until now.

"Looks like we don't have to worry about Satan feeling regret about his pact with Yuki," Asmodeus said.

"Huh!? You thought I was disappointed or something!?" Satan grimaced.

-End-