sunk cock fallacy

When you invest a lot of time into getting to know a girl, find out you don’t really like her, but still do the seggs anyway because you've put that much time into it.

Person A: “I'm gonna seggs her tonight.”
Person B: “I thought you said you didn’t like her.”
Person A: “I did, but I'm horny, and I don’t wanna have to go back to phase 1.”
Person B: “Sunk cock fallacy.”