Question for everyone, about possession/protection in stories. Your impressions don't have to revolve around or be based solely on romantic sub/plots (RSP for easier typing), but in general, though it's most often
overused in RSP.
In case I need to mention it again, interpersonal dynamics are absolute fascination to me, especially when you add in any sort of imbalance of power. Given that, you may get already the gist of what I mean when I bring up characters being possessive or protective: it's most often the more powerful character, the one with little to obviously gain, who feels anywhere from unexpectedly protective (or the shadow-side version, possessive) of another character -- to the RSP style in which it's an almost obsessive and immediate protective/possessive sense.
( The question: at some point, in everyday real relationships, have you seen/experienced an overwhelming (or at least very strong) sense of needing/wanting to 'protect' a lover? )