Can shut eyes cry? [Closed RP with Pragmatic-mentality.]
Koishi couldn't tell what the weather was outside, but she knew it was a good day. She had come back underground to visit, and seeing her sister made it a good day in her book. She had even waved hello to Yuugi on her way down!
As for why Koishi picked this particular day to make the trek back home, well, she wanted to ask a particularly important question to her sister. Koishi valued her sister's intelligence very highly, even if she wasn't really the best fighter. She just hoped that she'd still remember the question by the time she arrived at the palace, after all, she wasn't the best at remembering things.
But after a good while of walking, as flying took half the fun out of adventuring, she made her way inside the palace, and up to the study where her sister usually lied dormant, writing one book or another. She took great care to sneak into the study, as her sister was the one most sensitive to her presence, no matter how small it was. Hoping she would catch her sister by surprise as she wrote away, Koishi jumped into the foreground, and belted,
"Hey sis! Wanna help me write a book?"