Nigerian slang: Elderly man who uses the lure of a good time to seduce young girls (usually young college girls). Especially as they are working class and have disposable income that neither college girls nor their college boyfriends can compete with. A play on the word Aristocrat.
When I'm older, I'm gonna frequent this College dorm as an Aristo.
My Aristo is coming to pick me up today and we are heading to Tinapa for the weekend. See you girls on Monday.