Similar thing happened to me recently. In a bar, walked over to approach two attractive women - one had her back to me so I hadn't seen much of her. Turned out that the one with her back to me was someone I had been introduced to a few times via a group of friends. Luckily I remembered her name, although the look on her face when I said "it's... Julie, isn't it?" was priceless - she didn't remember me at first
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