'~이' is a particle you can put after adjectives to make it a noun and the noun signifies 'a person who contains the outstanding characteristic of the adjective, inside him or her' For example, 귀여운 = cute -> 귀염이 = A person who is so cute / 못난 = ugly -> 못난이 = A person who is ugly, 똑똑한 = smart -> 똑똑이 = A smart guy or girl, and so on 상큼한 = fresh -> 상큼이 = A fresh person (Being fresh doesn't mean literally fresh in terms of expiration date or so. It rather means a person is pure, young, cheer and attractive rather than overshadowed by conventional bullshits or depression) Please note that not all adjectives can make ~이

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a vibrant person who emits positive energy.