A/N: A while ago I had a chat with a friend of mine who's studying for textile engineer. She knows craploads about fashion and fashion history, and I took the opportunity of asking a bit about Mephisto's peculiar wardrobe. The result put pictures in my head that I simply couldn't get rid of.

This is canon for TEotB, and chronologically set in between ch 94 and ch 95. Why I'm not putting it in the main fic? Uh... It's going to be long enough already without little behind-the-scenes detours like this one. x')

I do not own or profit from any of what Kazue Kato has created.

Habits, as all knowledgeable people should be aware, are dangerous things. Routine hides in the flesh like a parasite, and dulls the sharpest mind with habitual behaviour to prevent scrutiny and uprooting. Anything can become a habit: the danger lies in not being aware of habits, and thus not being aware of where they might lead. Most are harmless; some are beneficial, some are detrimental, some lead to new discoveries…

Sleepovers in Faust Mansion were becoming habit, and for good reason: the comfiest bed in the country, the greatest selection of films any private person owned, and a nine course breakfast buffet awaiting in the morning. The only drawback was Mephisto, really.

"Assssss-haaaaaaat…!" Shiro hissed as he slowly fumbled his way around the bedroom for the third time. He was used to having his lighter confiscated when he visited, but to wake up in the morning and not be able to find his glasses was a different matter. "Why do you have so bloody many toys, you twit?" It was nothing short of a miracle that he hadn't knocked anything down yet. He'd looked everywhere, even inside the display cases that held the principal's most valuable pie- "Ouch!"

The button-eyed plushies looked innocently at him from atop the drawers he'd banged his foot against. …and only then did it strike Shiro as odd that Mephisto had drawers, when he had a walk-in wardrobe twice as large as the dorm room Shiro lived in.

"Scarves." Heh, so that was where his lighter landed? Good to know for future sleepovers. Shiro pulled out the next drawer: "Socks." No, not really. "Oh Mephisto, you're unbelievable…" Shiro lifted up one of the striped stockings between his forefinger and thumb, and still couldn't quite grasp that it was silk stockings. "My god…" With something in between an embarrassed laugh and a snort he put the stocking back and proceeded to the third drawer.

…and after the initial shock, he laughed. Hell yeah. If the old goat spirited away his glasses it was only fair that Shiro should get to enjoy the search for them.

"Of course you're the kind to keep trophies, you horndog." One, two, three – no, he couldn't count how many there were. "Seems you like ladies with slim waists", Shiro snickered to himself as he admired an especially delicate lace garter belt that had a pleasant smell of lavender about it. "The Vatican's obedient guardian dog indeed."

"Obedient in all that matters", Mephisto's rich voice replied from the bedroom door. "Pray tell; why are you going through my drawers…?"

"Pray tell; where did you hide my glasses?" He pushed the drawer shut and faced the talking blob. "I'm a wee bit handicapped without them."

*poof*

"You left them by the bathroom mirror", said the in-focus Mephisto in the doorway. "Yare yare, humans blame demons for all kinds of things."

"And more often than not, we're right in doing that." Shiro adjusted his glasses and nodded his head at the drawers with a smirk. "A habit of keeping mementos, huh? Quite the collection of good memories there. She must've looked smoking hot in that lacy pink one."

An unusually blank look crossed the demon's features. For a moment it seemed like he was at a complete loss for what Shiro was talking about, until that look bloomed into the most lecherous smirk Shiro had seen in his life.

"Well well: I know what I'll be wearing next time you sleep here, then~"

And gradually… Shiro's face came to match the pink garter belt.

"No… Shit, no…" But the pictures kept flooding his mind, one worse than the other, and made his face crinkle up in pain. "Oh god…" He covered his eyes, but kept seeing Mephisto in… in… "I can never look at you again, you pervert!" he groaned from the floor where he had collapsed, rolling back and forth as if plagued by invisible insects that he desperately wanted to crush. "Why the hell are you wearing women's undergarments?!"

"Women's?" Mephisto snorted and crossed his arms. "I'll have you know that garter belt and stockings were the finest haute couture a man could own in the 1550's."

"This is the twentieth century, you ass!"

"True fashion is ageless: garter belt and stockings are still in high demand", he said in blithely lilting tones.

"For women!"

"Indeed: history is often gravely misunderstood by future generations."

"It's you who're misunderstanding contemporary society", he groaned into his hand. Rolling around didn't help, only made him motion sick on top of the general… discomfort.

"Are you sure~?" The demon grinned all the way out to his pointy ears. "I hear contemporary society thinks I'm smoking hot in lady lingerie."

Habits are dangerous things. Most are harmless; some are beneficial, some are detrimental, some lead to new discoveries… and some lead to discoveries you'd rather not make.

A/N: Mephisto's trousers and stockings date approximately to mid 1500s: and if they do, then he is wearing a garter belt with them. x)

As a curious anecdote, I worked this into my cosplay, even if that (fortunately!) doesn't show. I can recommend anyone doing Mephisto's principal uniform to include attaching points for garter belt straps in the stockings. It works miracles.