You're Yuuka Kazami in her previous era as the mistress of the mansion Mugenkan at the boundary between Gensokyo and the Fantasy World, guarded by two gatekeepers - Elly and possibly Kurumi.

Since Kurimi barely lets someone enter your mansion, you live a quite peaceful and quiet life. One day, you were preparing to have a nap when Elly knocked on your door while entering, she seemed bored and wanted attention

"Hmm~? Mistress Yuuka, Mugenkan is becoming quite lonely, only the two of us, because Kurumi barely lets someone pass; I'm getting rusty, y'know~?"