Trying to remember the name of this one omegaverse

There was a omega, who is trying to save his brother who was selected for some sort of partnering. They came from like an omega zone where they were all sort of confined together. While trying to find his brother ran into this guy (alpha) who said his mother was someone important. There was a painting of a dog, and he said it was his mother’s dog, and he may have been lying. Basically, the alpha said that he should take his brother’s place if he wanted his brother to not be selected.