I love the feeling of intense passion in stories, so I'd say I lean toward faster pacing.
I can absolutely enjoy very slow, step-by-step narratives as well. I read manga chapter by chapter.
However, when things move quickly in romance, it immediately grabs my interest. A vivid, dynamic presentation really works for me.
It doesn't necessarily have to be a romance itself, but it's important to me that the chemistry between the characters clicks right away. The pacing can slow down later - that's actually great - but that initial spark of interest between them matters most.
Maybe that's why I'm especially drawn to demons - they usually want to devour the main character right away, and only afterward do their feelings grow deeper, evolving from that original instinct