Maiken:

An adult Maiken is near indistinguishable from a human. However, when you get closer you may notice a few differences. Their eyes often have strange patterns in them. Very similar to those of a frog's eye. They have elongated tongues that they can use as a defensive mechanism. Larger muscles in their legs. In fact one of their ancestors seems to have been a frog. It is quite the mystery how they developed into their current state.