The blue tail is the proof of kid.

The Japanese Lizard is a familiar lizard that often bask in the sun on stones to rise their body temperature. Same as the Japanese Grass Lizard, when they are in danger, they detach their tails and run away from enemies. They are often found in areas with more soil than the Japanese Grass Lizard, and the surface of their body has a wet texture.
When they are young, their entire body is black and their tails are blue, but as they grow older, their bodies turn brown. If you see one, it will quickly run away, but if you wait for a while, it will often return to its original spot.