I come around when you least expect me
I'm sitting at the bar when your glass is empty
from Childish Gambino – Heartbeat Lyrics on Rap Genius
Meaning
He is always showing up when she least expects it, possibly even stalking her.

But more likely, he’s not physically around her, he just keeps coming back into her thoughts. She thinks of him when she’s been drinking: “when your glass is empty.”
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