My friend has this bl manhwa she’s reading but won’t tell me what, any guesses?

This may sound really petty, but I’m determined to find out what it is because she said it was “too freaky” for me. Keep in mind, we have read Mr. A’s farm together. So I think we are past the point of “too freaky”. The manhwa she’s reading is known in community for being freaky, is a bl, the ml is respectful(she has weird standards so I don’t trust that statement much), fine, and also murders people in his free time. And no it isn’t kill stalking. Keep in mind this is a bl too. Any suggestions? It has to be something she’s really ashamed of to hide it from me😭