Some TMNT stuff was always meant for grownups.
In the original comics, Raphael was shown to be the most aggressive, tempered, violent, and competitive of the Ninja Turtles. You could almost call him a typical teenager, he often feels misunderstood and believes that he is alone in the world.
It is Raphael who is sent to issue a challenge to the Shredder by Splinter, and as he infiltrates Oroku Saki's security business, he kills several thugs. It is clear that he is the most aggressive. The Turtles return to their sewer home after the Shredder is killed.
When the Turtles rescue April O'Neil, who is an assistant to Mouser developer Baxter Stockman, it is Raphael who knocks him unconscious. After Stockman has the Mousers destroy his building, the Turtles return home to find destroyed Mousers and Splinter missing, April invites them back to her house.
In the earliest black-and-white Mirage Comics, Raphael was the most violent turtle and had a tendency for going berserk either in battle or when his temper flared up. His anger often brings out the worst in him, as one time he almost smashed Michelangelo's skull in a sparring match. His anger and stubbornness also causes him to repeatedly collide with Leonardo. He has a somewhat cynical and sarcastic sense of humor. In later issues, it's shown that he is not particularly fond of "Supernatural," stating it up front in Tales of Raphael: Bad Moon Rising.
Raphael mellowed somewhat as the series went on. Possibly a key moment for his character development was when he allowed Leo to go in alone to defeat the Shredder after nearly being killed by the Foot Elite in issue #21 of Volume 1. Since then, he has been less likely to challenge Leonardo's leadership, and on the whole is more friendly towards his family and allies.
Of his three brothers, Raphael is closest to Michelangelo, even having stated it in the fourth issue of the original TMNT comics. Raphael often shows a caring, more laid-back, side of himself when around his brother, even if he often annoys him, frequently indulging the younger turtle emotionally when at home and ferociously protecting him from harm when in battle. Raphael openly admits that the mere thought of his youngest brother being grievously injured causes him to experience violent rage. In his self-titled one-shot micro series, Raphael met human vigilante Casey Jones, his foil, who was even more violent and unstable than he was. Despite their brutal first meeting, the two have since formed a close bond and friendship.
In the comic book series' Volume 4, he is still the most violent turtle, but is more sociable. After having been bitten by a vampire-like creature in issue #12, he experienced a further mutation, and became a large, dinosaur-like version of himself. He went into a state of berserk animal rage because of it, but with some guidance by an inner manifestation of Master Splinter, he regained his original mentality and later assisted Leonardo and Casey Jones in tracking down the vampires who attacked him. This is also somewhat similar to an earlier storyline during Volume 1, where Raphael was attacked by a leech-like creature who, when sucking his blood, also drained him of the mutagen in his body and reverted him to a small turtle. The leech itself mutated and vanished, prompting the remaining turtles to follow it. Finally, after tracking down the creature, Raphael manages to bite it and pierce its skin, thereby drinking its blood and mutating back.
This Raph briefly appears in Trans-Dimensional Turtles.
Perhaps the most telling description of Raphael can be found within April O’Neil’s journal. She once wrote that Raphael scared her, and that he was very “unbalanced” and “unpredictable.”
Generally speaking, Raphael is a loose cannon. He doesn’t respond well to authority (with the sole exception of Splinter) and does whatever feels right to him at the time.
His temper is legendary. Like many other characters in fiction he seems to suffer from a form of Intermittent Explosive Disorder which causes him to break out into a murderous rage whenever he is frustrated or in combat. He has turned this anger on his friends and foe in turn, but usually shows true regret when he has done so on the latter.
It is this single aspect of his personality, and his unusual energy levels, that make Raphael the deadliest of the 4 turtle brothers. Despite the explosiveness of his temper (and utter brutality in battle), Raphael is loyal to a fault and quick to forgive his friends.
Raphael’s relationship with his brothers and extended family is quite simple. He has a particular soft spot for both Michelangelo (who is often his playmate) and Casey Jones (who he considers the fifth Turtle brother). He deeply loves and respects Splinter and enjoys teasing Donatello. And then, there’s Leonardo.
As time has passed, Raphael’s impatient and volatile nature has chaffed at the relationship that he shares with his older brother Leonardo. Leo’s calm and steady nature often exists in stark contrast to Raphael’s, and like most siblings the two have exchanged heated words and blows over differences of opinion.
It is clear though that Raphael does love his “older” brother and even has a grudging respect for him.
- He used to have a teddy bear named "Brown Bear".
- In issue #3: The Great Chase, he asks April if she has any beer. He is 15 in this issue, and the minimum age to drink beer in the state of New York was 19 years of age between December 1982 and December 1985 (now 21 years of age), making him under age; however, he fell asleep before he had any beer.
- In IDW Publishing's colorized reprint of Kirby and the Warp Crystal, Raphael's eyes are portrayed as blue.
- As shown in "Day in the Life", Raph and his brothers are all fans of Bruce Lee.