There's a lot of time I've been asking about this same question in some of the post here, but seems that much of the people here are so busy in GPU mining, well I understand that because some of the coin that was started in cpu is now enabled to mine by GPU, so what is the point that we are competing gpu farm mining our favorite coin.
There's only few options to mine profitable with CPU and only in certain conditions, this is the reason people don't talk a lot about
XMR and VRS are the coins that can give you a real profit, there's anore coins minable by CPU, but not so profitable, you can always mine and hold until coin reach a good price
But let's talk about these 2 coins
If you have a Ryzen, and a rig with some GPUs mining, it's easy to gain some money with CPUs, because the power consumption will only increase a little, you already have Motherboards, rams, GPUs, ssd etc running, so it's profit
If you have laptops, most of intel cpus, older processors, or only a basic PC, it's doesn't worth to mine with CPUs, you'll put all your PC components to stress, waste power and only "gain" a few cents