Komainu
In the early Heian period (ninth century), the tradition of the statue pairs changed, and they started to look different and have different names. One of the statues had an open mouth and was called shishi (獅子, which means 'lion') because it resembled a lion like before. The other statue had a closed mouth, looked more like a dog, and was called komainu or "Goguryeo dog". Sometimes, it even had a single horn on its head. Gradually, the animals returned to being identical except for their mouths and were called komainu.