My name is Sketchy!

Sketchy is a sweet, soft as silk, pretty kitty. I am hoping that finding him the right home will cure him of his worries.
We adopted Sketchy and his brother when they were about a year old, already spayed from the facility they were acquired from. Shots up to date.
Sketchy needs a quiet house without other pets or kids. He gets too frightened. He spends most of the day sleeping away somewhere hidden. He loves to come out when the house is quiet and we have settled on the couch, where he comes to sit beside us and get his belly rubbed. He is a vocal cat at this time, requesting attention.
As the brother cats aged they started to not get along. We have tried everything the vet and we and internet can think of to try to keep them happy and cohabiting but it is only getting worse. Sketchy is spraying, Im guessing to mark territory from his brother and they are fighting. They have been on a special prescription diet and both taking Fluoxetine to try to ease their worry/animosity.