BookTok is obsessed with morally grey heroes right now. What do you think actually makes one work?

Dark romance and romantasy are full of them — the villain love interest, the captor, the man who does terrible things and somehow you're rooting for him anyway. BookTok can't get enough.

But there's a difference between a character who's genuinely complex and one who's just cruel with good cheekbones. The grey ones that actually work usually have some kind of internal code, even if it's broken. You understand why they do what they do, even when you shouldn't.

What makes a morally grey character compelling to you versus one that just feels like an excuse for bad behaviour? And has anyone written one on Pirr that surprised you?