A. Phex Brothers

The Aphex Brothers (エイフェックス兄弟) are minor antagonists featured in JoJolion.

They appear to be hunting Karera Sakunami, presumably for her knowledge concerning the Rokakaka fruits.

Appearance
Besides the elder brother's crippled right hand, both are identical in appearance and attire. Sporting nearly shaven heads with intricate sideburn designs and pierced ears, they wear long-sleeved decorated shirts and shorts which are reminiscent of typical footballer clothing.

The deformity in the older brother's hand resembles the "equivalent exchange" aspect of the Rokakaka, hinting at the possible motives of the two.

Personality
The pair share a duality described as harmonious with one another, being based on the Japanese concept of 'A-un', which explains the connected nature of opposites and their seemingly contradictory similarities.

Aside from that, the elder of the two brothers seems to be the one in charge, and was the only one to speak at first, but the younger brother speaks as well later on. The elder brother is the one who communicates with the policemen in place of his brother and the one who displays a Stand power;  his brother however would later reveal he also possessed a Stand - hidden in his soccer ball bag. The younger brother is more reserved, preferring to let his older brother do most of the talking. The younger brother also has a habit of kicking around his Stand's container and performing tricks with it, not unlike a soccer player.

Stands


The elder of the two brothers has utilized his Stand Schottkey No. 1 on multiple occasions and it has become apparent that the function of his power is to shift objects touched with his left hand to the stub on his right; wherein he can manipulate the way it materializes for a variety of strategic advantages.

The first example of this is shown during the confrontation between the brothers and a pair of police officers who attempt to ascertain the identity of the brothers. Objects transported in this fashion will seem to break down and crumble while the material reassembles on the other end. The younger brother's Schottkey No. 2 possess the ability to release potentially fatal toxic gas whenever the Stand's container is opened.

Rock Physiology
While similar to a human's, their bodies can presumably change into rock. Because of this, they do not need to sleep or rest. They can mimic rocks to the point that it makes them indistinguishable from them.

Norisuke theorizes that Yotsuyu's physiology requires him to have at least a small amount of skin respiration and in the absence of such his body structure will begin to break down due to it becoming less structurally stable than an ordinary human's. This could be a trait shared by other Rock humans, including the Aphex brothers.

Miscellaneous
The younger brother demonstrates versatile and dynamic control of his soccer ball common of experts, capable of moving it between his legs and head effortlessly and kicking it with enough force and power that it could be considered an attack of its own.

Synopsis
The pair are first observed performing tricks with a soccer ball in the streets of Morioh as Josuke and Karera walk on, to the amazement of the gathering crowd.

As Josuke and Karera walk away from the ATM, the brothers can be seen questioned by a pair of policemen as to the strange nature of their ball and what one officer perceives to be a rock held in the hand of the older brother. After he demonstrates his ability in subduing the policemen, dialogue exchanged between the two brothers suggests that they have been hunting Karera and are surprised she has lasted this long.

Searching the streets for people who have come into contact with Sakunami, they eventually run into her and Josuke when the pair are nearing Kira's apartment, and the younger brother acts as a distraction while the other grabs Karera from behind and uses his ability to transport the fuel in a car's tank all over her, proceeding to set her ablaze if not for the intervention of Josuke's Soft & Wet.

At the realization that Josuke appears to be a more pressing threat they decided to prioritize him as their target while allowing Karera to escape, more fixated on discovering the identity of the strange and powerful man who also has ties to the Rokakaka fruits.

Trivia

 * They draw minor similarities to the D'Arby brothers.