Dr. Shamal is a crazed womanizer who hits on every cute woman he sees. Though often unsuccessful, he is always seen hitting on one woman and then instantly moving on to flirt with the next woman that passes by him. He is said to be hiding in Japan after flirting with a queen, charging him for putting the moves on 2082 women simultaneously.
Putting aside his normal attitude, Shamal happens to be a notorious assassin called "Trident Shamal" and is also a renowned doctor who refuses to treat men. Reborn claims Dr. Shamal had a hand in handling his (Reborn's) birth. Later in a flashback, Reborn states that Shamal "erased" Reborn's old self after he had accepted his new Arcobaleno body. He uses Trident Mosquitoes, one of which is named Angela, to infect his targets with deadly illnesses. His assassination skill is so great that he was once asked to join the Varia. Also, since he naturally contracts viruses and diseases easily, he carries 666 pills that contain Mosquitoes infected with deadly diseases. He claims to be infected with 666 diseases, but is not dead because all his diseases negate each other. An example would be if he had a disease that rapidly decreases body temperature, then he has another one that increases it. Shamal also happens to be the one that introduced Gokudera to Bombs when he used to work for Gokudera's old Mafia Famiglia. Gokudera initially wanted to learn how to use the Trident Mosquito, but Shamal taught him how to use mid-ranged Weapons instead.