He knew that right after eating the fruit there had been a strange sensation in his crotch, intense enough to cause him to get an erection, but there was something wrong with the way it felt. He couldn't quite figure it out, but it was very different from the way things normally felt, maybe more intense than normal, or maybe something else. Unzipping his pants freed his erection.
He had grown a massive boner, so hard that it could be made of rock, big and veiny but most importantly, completely black. It didn't look like his former one at all, except for the slight curve it possessed and the veins positions that ran down its length. Not wanting to believe what he saw he touched it and determined that it was very real. Afraid of what else he might find, he examined his balls and let out a sigh of relief when they turned out to be unchanged.
One normal erection he would have been able to ignore and hide before going back to his friends, but it he didn't think he'd be able to stuff that cigar back into his pants. With nothing else to do he took it with both hands and began to masturbate.
The sensations and pleasure was doubled by his having such a big cock. His whole world dwindled down to the huge blissful aches at his crotch. He wasn't used to giving hands such a workout, since he'd never been able to use both together before, and realized that he was quite able to get to the point he needed to be at. Never before in his life had he needed to cum so badly. Rubbing harder wasn't helping since his right hand, the one he used less in such activities, was starting to get tired. To solve this problem he tried to put his hands together to use them on the same spot at the same time.
At first the feeling of the big black cock smashed so hard and throbbing so vigorously repulsed him, but the pleasure only intensified with each throb, bringing him ever closer to the orgasm he craved.
The rush of blood pounding through his cock seemed to intensify, driving him to his knees as it tensed before he shot a huge stream of cum across the room.
Afterward he realized that though the massive orgasm had been twice intense as any he'd had with his former cock, the resulting spurt of cum were just farther of what he was used to. It was the obvious result of having the big black cock with his regular balls, not that he'd want a set of big black balls. It was still repulsive to him.
Realizing that the fruit had done this to him he pondered what he would do.