Mermaid Clock

A given time before you realize that you wanna bone a female that you don't have any sexual or romantic feelings towards, even the most unattractive chick you see daily can in-fact have a "Mermaid Clock"

Dave: "yo look at jessica ?" Cam: " yeah she's ugly asf" Dave: "dude wait until she hits her mermaid clock"
Cam: "what's that dude? Dave: "It's when you hang around her so much you start wanting to bone her even if you don't have physical attraction towards her"