Most of us display narcissist traits at one point or another; it's a condition that exists on a continuum, which can change according to personality type but also due to specific circumstances and life events. Research suggests that, at the extreme end of the scale, Narcissist Personality Disorder is rare, and more prevalent in men. Scientists believe it likely to surface in the form of someone who "engages in risky behaviour, holds an unrealistic superior view of themselves, is over-confident, shows little empathy for others, and has little shame or guilt". These traits are likely to show themselves in different ways, but in a relationship, they may appear within a need for constant attention or affirmation, a sense of entitlement and controlling tendencies.
To make the situation more confusing, narcissism can also have positive effects in relationships. A 2018 report from the University of Louisiana found that all kinds of narcissists, along with manipulators and psychopaths, (the so-called "dark triad" of personality traits) are capable of being caring towards others; as long as they see benefit to themselves in doing so. Similarly, experts believe that, on a sliding scale of narcissism, more "prosocial narcissists" are driven by their overriding desire to be liked, meaning they are fun to be around, and take a lot of satisfaction in your positive reaction to them. The key amid this maze of manipulation is to step back and recognise your partner's behaviour for what it is - to separate your own emotional responses from what's really going on. If someone you love has narcissistic traits and it's beginning to feel like they're manipulating you, take distance and start a record of their behaviour.
That way, you can build a picture of toxic "micromanipulations" for what they are - a controlling tactic - and break free to healthier ground.