Someone who acts like they're shit in a really egocentric way. They think they're all that when actually others think that they are just self-centred and narcissistic. First world bitches only care about themselves and the material possessions they have, they don't care about anyone one else (especially those who are poorer than themselves) as they live in their 'first world' lifestyle.
OMG, that girl just posted another selfie on Instagram. She is such a first world bitch.

Honestly, that first world bitch should spend some time doing something useful to help others instead of wasting time looking in a mirror.
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