Morally Grey
A morally grey character is one whose choices can't be filed neatly under good or evil. In romance it is usually the love interest: dangerous, loyal by his own code, and willing to cross lines for you that you would never cross yourself.
The term caught on because readers needed a word for the pull that spotless heroes don't have. Grey is not weak. It means the character has a morality, just not yours, and reading him means deciding how much of it you're willing to carry.
The tells are consistent. He doesn't lie to you, but he doesn't tell you everything. He protects what is his, and the open question is whether you want to be counted as his. His capacity for harm never points at you, but it exists, and you know it.
Dante in “Under His Protection” offers you the shelter of the family, and you can tell that protection is not all he wants. The publisher in “The Antiquarian's Debt” negotiates your brother's debt with impeccable manners and an unsettling calm. In “Nightclub of Shadows” you are the undercover investigator whose cover the club owner sees through in a second, and she hires you anyway.
Morally Grey at Everglow
Related terms
Morally Grey, but you decide.
At Everglow you do not just read it. You are the protagonist, and every chapter ends with your move.