Tora stands for tiger and « rin » for RInpa the Japanese school of Japanese painting.
It comes from this painting by the Rinpa school painter Ogata Korin (1658-1716).called Toranozu This ink painting shows a sitting tiger between bamboo shoots. The face of the tiger seems to be smiling itonically.
Torarin tweets https://twitter.com/TORARINOFFICIAL
has a blog and a website