Here's how he'll pay for his horrible acts.
People who care about the prostitute might retaliate by going after him, if he's still alive, or going after someone he cares about. If that doesn't happen, and word gets out about what he did, people closely related to him would suffer the discrimination and would be shunned because people are afraid of them. The publicity itself would be enough to ruin family businesses and friendships. Even family members would disown him. But this dude will probably go on with his horrible plan because anyone crazy enough to hatch a plan like that clearly doesn't care about anyone else. But the things I mentioned would still happen, and it'll make it harder for his offsprings to have successful relationships and have kids and eventually his gene will die off from the population.
People who care about the prostitute might retaliate by going after him, if he's still alive, or going after someone he cares about. If that doesn't happen, and word gets out about what he did, people closely related to him would suffer the discrimination and would be shunned because people are afraid of them. The publicity itself would be enough to ruin family businesses and friendships. Even family members would disown him. But this dude will probably go on with his horrible plan because anyone crazy enough to hatch a plan like that clearly doesn't care about anyone else. But the things I mentioned would still happen, and it'll make it harder for his offsprings to have successful relationships and have kids and eventually his gene will die off from the population.