between 1:30 am and 4 am. when a girl/guy will text you specifically at this time because they know that you're probably up, possibly thinking about them, not distracted with too much, and probably in a somewhat sappy, vulnerable mood, ready and willing to get played like a mothafuckin fiddle.
damn brah, why'd she have to text me now? it's 3 am, she knows i aint busy, and this is the time of night that i miss her the most." --"she ain't a fool, it's vulnerable hour, perfect time for optimum culosoing, be strong, tell her to google that shit nigga.
by sweet black jesus April 4, 2011
Get the vulnerable hourmug.