[LawrenceT]

Yeah, Shiro is quite a common name for a pet animal in Japan.

As for Naga, well, it is a nice choice, but something is missing. Let me suggest Nagahiko (for a boy) and Nagako (for a girl). Nagahiko can even be a human name. "Hiko" is related to Japanese gods, so it is very exotic.

I am a student and a part-time translator living in Kyoto.