Kura
Mitsuki’s Grandma locks Mitsuki up in a “kura,” a warehouse. Rich families had these kuras to store food, or precious pieces of artwork, for example.
A couple times a year, there are TV shows where famous (Japanese and Western) antique dealers visit a “kura” of a rich family. The “we haven’t opened the box ever, we have no idea what’s in it” occasionally contains expensive pottery or painted scrolls.
Names
Mitsuki（満月）, Hazuki (葉月, Mitsuki’s mom), and Fuzuki (文月, Mitsuki’s grandma) all have the same kanji as the second character of their name.
This sort of naming names is fairly common. For instance, my mom’s named Chieko , and her sister is Michiko. The “chi” part is the same kanji, 智. The character for my “tomo” is also the same kanji, but read differently.
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