Towa no Quon 1: Utakata no Kaben, Zetman Recommendations
The main characters both have supernatural powers that they use to save people. The humanoid creatures in Towa no Quon and Zetman look quite similar. Both stories have dark themes, action and violence.
The main characters' powers are very similar, where their entire body transforms into some humanoid being which allows them to gain great agility and strength.
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