Rex Taroumaru

Taromaru Rex, a.k.a. T.Rex is an assistant photographer and the third member of Secret Aliens.
Tom's assistant photographer. He's impatient and easy to set off, but does his job seriously.

Shortly after he was born, he was abandoned at the foot of a T.Rex fossil in a museum, and grew up as a delinquent in an orphanage.

Tom, who believed Rex would grow up to become a miscreant at this rate, tried to recruit Rex as his assistant by having him stand up to attack by Hypnosis Microphone. After Tom wiped the floor with him, Rex ended up following Tom's words of "let's see the world together."

(Source: Hypnosis Mic Wiki)