1) She's a slut
2) It looks "cool"
3) It's just stupid

because that's how she rolls.

I do it too, but only on casual Fridays.

maybe its a glitch?

It's not a glitch and it is NOT underwear. The game was made in the early 90s and in the late 80s/early 90s it was quite popular to wear lycra outfits to work out in. Many of them had a pair of briefs that would be worn over a pair of lightweight lycra leggings. It was also popular to wear leotards over leggings. It was the style of the time. Sonya in MK1 is a walking poster child for early 90s gym style. You could walk into any gym in the country at that time and find the exact same outfit.

Question answered. Thread closed.