Eruka Frog is a frog-themed witch who serves under Medusa Gorgon. Like many other witches, Eruka craves destruction and enjoys the fact that she was born a Witch. However, she is extremely cowardly, preferring to flee rather than fight, and never hesitates begging for mercy when cowed. She can also be considered clingy to her partner, Free, even becoming needy and docile. Despite her malicious intent, Eruka has an earnest disposition with other Witches, including Mizune, with whom she is close friends with. She can be demeaning to those whom she considers inferior, though.

Magic:

- Transform: Eruka transforms into a frog. She can still talk in this form.

- Egg Bombs: Tadpole-like black balls with frog faces that can hop towards their target before detonating.

- Arithmetic Magic (Magic Calculation): Used as a 'place maker' for high level spells so they are more precise.