my brother's new gf is giving me the ick and I can't explain it

So my little brother (32) brought his girlfriend home, said they're the same age and dating. First time I met her I was like okay whatever, just got a weird vibe. Second time though? The red flags started stacking.

**1. Her vibe/appearance**

Okay first impression she was pretty. Like, flashy face, definitely eye-catching. BUT her energy was... off. Cold in a way that felt almost scary? Like when she got flustered or was being self-indulgent, her expression went completely blank and unsettling. And idk how to say this but she gave off these like... hostess bar vibes? (not trying to be mean, just describing it) She was dressed totally clean, nothing revealing, but the vibe was cheap somehow. Not in an expensive way. And it wasn't just me either. my parents and relatives all felt it too, unprompted.

**2. Hardcore Christian behavior**

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