Girls, is flexing muscle a turn-on or turn-off to you?

I don't mean like ridiculous, full-on bodybuilding posing or anything. I just mean like a quick flex to be cheeky. Sometimes I'll catch girls looking (esp when I have my shirt off) and I get the urge to show off just to see how they'll react. I caught a girl checking out my arms one time and tensed my arm muscle and she wouldn't make eye contact with me the rest of the night.
Girls, is flexing muscle a turn-on or turn-off to you?
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