Like his manga counterpart, Ryo has two forms while as Dante. One appearence based on his iconic design of the manga and another, more human-like form, which resembles that of Akira Fudo's Devilman form (the anime's take is, however, more deliberate when compared to the manga's version).
On the final episode, Dante achieved a new "Golden" form after being given the powers of his fellow demons. In this form, Dante is pure gold colored with Ryo Utsugi's face being more purified compared to his pale skin/red facial markings from his normal state.
In the beginning of the anime, Ryo starts off as very secluded and anti-social due to recurring nightmares. Like in the manga, Ryo takes awhile before accepting himself as Dante.
Unlike most characters by Go Nagai, Ryo Utsugi, as a human, is usually quite calm with nigh-apathy. However, after becoming Dante, he acquires a more aggressive personality in regards to facing danger.