Nice set-up, had me totally wondering what the defense was and then nicely explained at the end, but still keeping it part of the story and not just a staid, dry narration.
LoA

Sounds like quite a few boys I’ve met.

I can relate to this. I think at one point I used that particular defense against girls I liked. Kind of like how Chandler on Friends uses sarcasm to shield his insecurities.