Great characters have flaws, not just looks.
1. Start With a Wound
Abandonment, betrayal, hunger for control. Wounds drive obsession.
2. Tune Personality
Sliders: humor, warmth, aggression, mystery, flirtiness. A cold vampire with hidden warmth > generic nice guy.
3. Write a Greeting That Hooks
One line that shows voice: "The rain reminds me of you. Same cold, same longing."
Publish, test, iterate. Watch engagement score climb.