These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Ensemble Darkhorse: Nanaya's role in the early part of the original manga was fairly brief, but especially after the anime he seems to have grown considerably in popularity. Kairi Sorano herself is particularly fond of him, even casting him in her role for the "Sorano Group Workplace" crack segment. His Darkhorse status may have had something to do with his sudden reappearance much later in the manga, though it's hard to say for sure.