Despite their occupation, Yoshiro's parents wanted better for their son, and neither of them were as cold-hearted or vicious as their employer. Yoshiro was taught a certain pragmatic code of conduct as he grew up.
Yoshiro's parents eventually found a strange device that their employer was convinced had to do with an alien weapon of mass destruction. Accidentally triggering the genetic lock, they decided to shut down the device so that none of their associates could use the bunker/device for evil, and they encoded the genetic lock so that only someone with both of their DNA could unlock the bunker.
Yoshiro was sent off to keep him safe, and he found himself in Hawaii. Before the team's cross time adventure, Yoshiro was infected by Black Hand, and then picked up by the Feds for questioning about his parents. He died in custody, and was brought back to life as part of Amanda Waller's Project Fallback.
After altering their past, Yoshiro instead found himself at an ancient volcano, visited by Pele, the Hawaiian goddess of fire, who activated his latent powers and boosted them, tasking him with using fire to champion the world, with a special eye towards working against entropy and cold. Yoshiro was overwhelmed, and them was picked up by the Feds. He had any criminal past pardoned and was granted citizenship due to the deal he struck to work with Steve Trevor's office in the Department of Metahuman Affairs as a member of the New Guard.
Because of this, Fahrenheit's powers are both Metahuman and Mystical in nature. Originally Fahrenheit could project and control fire, fly, and could even manipulate cold and ice, when his powers were strictly metahuman in nature. Pele's modification of his powers eliminated his ability to manipulate cold, but added fire based illusions to his arsenal.
Fahrenheit is one of the youngest members of the New Gaurd. He often sets out with heroic intentions, but wars against the pragmatic self preservation taught to him by his parents. A pretty face causes him to loose most of his hold on logic. He is prone to cracking horrible jokes, and is fond of keeping trophies of the group's various adventures. He has developed an abiding disdain for Damian Wayne, especially since Damian recognized him and began referring to him as "minion spawn." This is a deviation from his normal concern for children, who he goes out of his way to protect due to his own less than ideal childhood.