A/N: Oh dear, too many plot bunnies. Must stop. Once again, I don't own the characters, they belong to Konno Oyuki.

Rereading this first chapter, I realised there were two inconsistencies: Yumi's age and how long she has known Sei for. Oops. I've corrected them!

"Whuuuuuhhh…" Yumi awoke, and immediately fell back to bed again. She'd never felt so groggy in her life. She felt quite drained of blood, actually.

'Ah! Yumi-chan! You're awake! Excellent!" A cheery voice chirped, way too chirpily for Yumi, right next to Yumi's ear.

"What is it, Sei-sama? WHAT!" Really, Sei-sama sometimes had the worst timing possible. All Yumi wanted to do was to sleep.

"Oh, c'mon, Yumi-chan. It's the beginning of your life! You know what that means!"

"Eeeeeh, SEI-SAMA! What are you doing in my room!?" Yumi had finally wokened up properly and now sat up in her bed. The words Sei mentioned lay forgotten within Yumi's mind.

-

A figure came and stood by Yumi's door. "Yumi-chan! Sei-san was just visiting- she wanted to see you on your big day."

"What big day, Mom? It's summer vacation, it's not my birthday, and I'm not due back in university until the end of this month."

"Well, just come downstairs and you'll know. By the way, do dress your best. Hurry up, Yumi-chan. Your brother's already almost done showering. It's his big day too."

-

"….Whuuuuh." Well, time to get up. She didn't want Yuuki to make her look bad by appearing downstairs much earlier than she did. Her mom sometimes went on flights of fancy sometimes, but with Sei here, it could actually be something important.

"That's my girl! See you downstairs in a moment. Or will you prefer me to stay?" Chirped Sei in a teasing voice.

"Go away, Sei-sama! See you downstairs! And Sachiko's not around, so I see no reason for you to be teasing me!"

"Ah, I just love seeing Yumi-chan's thousand expressions, that's all."

"…" Yumi turned around and scowled at Sei.

-

Sei grinned and patted Yumi on her head before leaving the room. "Right. Right, see you downstairs!"

Honour-student mode now switched on, Sei descended the stairs like a proper lady would.

Sei-sama. If they only knew your dirty old-man character.

-

Despite Yumi's disparaging thoughts about Sei, both of them knew that she did like Sei and cherished their friendship. It was just that sometimes Sei pushed things a little too far. But nothing Yumi couldn't handle. She considered herself quite an expert at dealing with Sei-sama's antics.

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