This does not look like a Russian blue. Russian blue have quite sharp facial features and tend to have green eyes, not so yellow-ish. Much more likely a British shorthair
Why is the Healin' Good Precure series tag added to this post? Well, let me tell you, this particular artwork of Madoka-chan is drawn in Healin' Good's artstyle, as well as the obvious fact that Yuuki Aoi, Madoka's seiyuu, also voices Cure Grace in that series, too.
Yeah, that's all you need to know. What I just said here is nothing new, everyone knows that.
