“An empath who only ever felt others' feelings — joining the Guardians is the first time she discovers her own.”
Physical touch lets her read exactly what another person is feeling — joy, grief, and everything in between.
Forces a target into sleep through touch — she briefly held Thanos at bay this way in Infinity War.
Can shift another person's emotional state — used mostly to soothe pain rather than as a weapon.
She lived inside other people's feelings while never knowing her own. Raised in isolation under Ego, she has no malice and takes the world exactly as it is. The Guardians are the first family she's ever had — and the first prompt for her to ask who she actually is. Awkward and earnest, but that combination is exactly what makes her genuine.