Thank you for your email. Without examining her or knowing more about her condition and history, I can't determine what might be going on with Mochi, but those are signs that she needs to see a veterinarian as soon as possible, as they will be able to examine her, decide what tests or treatments might be necessary, and treat her so that she feels better. I hope that all goes well for her.
The Russian blue is a sweet-tempered, loyal cat who will follow her owner everywhere, so don't be surprised if she greets you at the front door! While she has a tendency to attach to one pet parent in particular, she demonstrates affection with her whole family and demands it in return. It's said that Russian blues train their owners rather than the owners training them, a legend that's been proven true time and again.