Not much findable about this artist: Kobi (Japanese, active 19th century). Drawn with a brush in black ink, "with traces of pink watercolor" though I cannot see any, these stubby and intelligent-looking creatures reminded me of nothing so much as the fierce cats in Goya's Don Manuel Osorio de Zuniga of 1734. (You know that one - the little boy in red with a pet bird, and three ravenous kitties, one reduced to a pair of burning eyes in the dark.) That doesn't surprise me, since Japanese folklore makes the moon rabbit responsible for creating the elixir of immortality. Quite a responsibility, but these two look like they could take it.
You may see this piece at the Fine Arts Museums of San Francisco.