You've been staying at Eientei due to a minor but time consuming injury... plus some other unspecified reasons, Eirin had been rather vague. Still, you did meet Kaguya there... apparently she's a former moon princess, and had some legend tied to her, you're not entirely sure, you'd never heard it.
One day, as you step out of your room, just laying there on the ground are 5 items... There's a jeweled branch, a fan, a gem, and some other stuff. Deciding to err on the side of caution, you just take them into your room and leave them there, then proceed about your day as normal.
However, you immediately run into Kaguya, who looks extremely giddy... until she looks at you and mutters something about there being something missing. Still, you keep finding her throughout the day, which is strange considering how normally she just stays in her room.
At night, when you drift off into sleep again, you suddenly get nudged awake, only to find Kaguya kneeling besides you.
"Hey... I... I left them right there for you... Why did you not... Am i..." You can't exactly see why, but she sounds distraught.