But. . .Only by people I love, STRICTLY. If some weirdo comes and touches my hair, I'll probably punch 'em in the face, and I don't mean that as a figure of speech.
If my mum plays with my hair, I feel she likes it and it boosts me.
If a lover plays with my hair, I feel like it's a bonding experience.
If a (close) friend plays with my hair, I feel pampered. ^_^