The phrase "perverse pleasure" refers to finding enjoyment or satisfaction in something that is considered unusual, immoral, or unacceptable by most people. Full definition
I enjoy it, not because any great scientific revelations are there, but several vegans are active and I get some sort of perverse pleasure in taking aim at. (deniseminger.com)
These days, we expect those with firearms to use them to protect the innocent, not to destroy the helpless — much less to derive perverse pleasure from it. (politics.co.uk)
Still, I take perverse pleasure in telling that story. (moneysense.ca)