Stop wearing leggings with nothing but a t-shirt! It looks stupid! Your bum is all-hanging out there, and it makes everyone feel awkward, believe me.
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And I'm not saying this to be mean, honest. I know how you feel. I too am often a victim of trends. I wore tight midriff shirts in the early 2000's, and thought I looked great. But I was an eleven-year-old girl, not Jessica Alba, and could not pull off the look and greatly regret it now.
Which is why I am telling you before it is too late:
This leggings/t-shirt thing? It's just a fad. You will look back on it in ten years just as your mother looks back on her eighties prom disaster, with chagrin.
Yes, I realize that shirtdresses exist. And actually, they can look very good with leggings underneath. But that does not mean all t-shirts can be used as dresses. Nor do skinny jeans advocate even skinnier leggings. Because let me tell you, there is a big difference between showing off your pegs in a pair of jeans and looking like a naked orange thing.
I don't want to see your butt. You won't either. Trust me. It's for your own good.