Nouns

(n)eccentric, eccentric person, flake, oddball, geeka person with an unusual or odd personality
(n)character, eccentric, type, casea person of a specified kind (usually with many eccentricities)“a real character”, “a strange character”, “a friendly eccentric”, “the capable type”, “a mental case”

Adjectives

(s)bizarre, eccentric, freakish, freaky, flaky, flakey, gonzo, off-the-wall, outlandish, outreconspicuously or grossly unconventional or unusual“restaurants of bizarre design — one like a hat, another like a rabbit”, “famed for his eccentric spelling”, “a freakish combination of styles”, “his off-the-wall antics”, “the outlandish clothes of teenagers”, “outre and affected stage antics”
(a)eccentric, nonconcentricnot having a common center; not concentric“eccentric circles”