idiosyncrasy
a behavioral attribute that is distinctive and peculiar to an individual
innocuous
not injurious to physical or mental health
orthodox
adhering to what is commonly accepted
prosaic
lacking wit or imagination
quaint
attractively old-fashioned (but not necessarily authentic)
rarity
something unusual -- perhaps worthy of collecting
singular
being a single and separate person or thing
trite
repeated too often; overfamiliar through overuse
usual
occurring or encountered or experienced or observed frequently or in accordance with regular practice or procedure
unusual
not usual or common or ordinary