Even though Dante's look may change, there are certain qualities that stay constant across all mediums:
...White Hair Dante has white/silver hair which, combined with his icy blue eyes and pale complexion, immediately jolts your out of the mundane and into the exotic. It has the ethereal, otherworldly quality that contrasts advanced age with a youthful appearance. Someone timeless and immortal, and obviously supernatural. In this case, Dante's lovely silver locks are a by-product of his demonic heritage - a pretty common trend in Japanese pop culture. Unlike his brother Vergil, Dante's hair falls onto his face rather than being brushed away. It is short and straight in DMC3, slightly longer in DMC1, and even longer and fluffier in DMC2.
...Red Coat Dante's signature color is red. He wears red and he bleeds red... very red. Red being the color of passion and good fortune in Japan, as well as the traditional color of the hero. He favors trench-coats, often with a lot of random straps and silver fixtures hanging off of them. He must also have a large supply of spare trench-coats, because they keep getting torn to shreds every other scene. Dante appears to progressively lose clothing from game to game. In DMC1 he had a full trench-coat and shirt ensemble, in DMC2 he wore a black vest on top of the trench-coat, and in DMC3 he lost the shirt/vest altogether, settling for a lone strap across his bare chest. The latter has come to be known as the "nipple-warmer outfit" in some circles.
...Demon Blood Dante is half demon, which means his body reacts to pain and injury differently from a mere mortal. Whereas if a regular human were to get skewered by multiple scythes from several angles they would likely fall over, Dante shrugs it off and puts the shiny pointy things sticking out of him to good use against his foes. Though typically a sword dislodging itself from a statue to fly at you and impale you through the heart would mean certain death, Dante understands that this is simply the sword's way of saying "Hallo there, friend! You can wield me now! :-)" This isn't to say that the results aren't messy. Dante bleeds gallons of blood (and is fashion-conscious enough to wear matching colors), but his body is designed to take great amounts of damage and heal it very quickly. Still, he seems to be quite sensitive to being run through with his brother's slender katana.
...Devil Trigger Though Dante looks like a (really hot) human on the surface, the demon blood bubbling underneath sometimes boils over to unleash his darker form. It is called Majin form in Japanese and Devil Trigger in English. A verifiable powerhouse of demonic might, Dante becomes even more impervious to damage, he runs faster, his attacks become exponentially stronger, and his natural regeneration goes into overdrive. The potential to trigger this unholy adrenaline rush builds up with the amount of pain he gives and receives. It is a kind of fight or flight response, typically saved for getting out of extreme situations. If charged up beforehand, it releases a devastating demonic blast that damages and knocks down any enemies in the vicinity. The story of how Dante awakened to this form is told in the prequel DMC3, where after losing his first fight with Vergil and being left for dead, Dante springs back to his feet pulsing with renewed vitality.
...Style Everything Dante does he does with an impeccable sense of style. His renowned agility, dexterity, and grace is breathtaking to behold. His every movement is perfectly balanced and in complete harmony with his intention. His extraordinary skill with every weapon he gets his hands on reveals a flawless union of mind and body. The light-footed dance with which he traverses the screen, the smooth sleight of hand which which he maneuvers his guns, the trail of wafting red coat and bouncing white hair that follows him creates a mesmerizing spectacle that I can not tear myself away from. I can watch it all day, all night, take breaks only to sing his praises to others, and always come back for more.

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