My sister who always wears my clothes without asking. She's petite, the complete opposite of my large frame. When I saw her wearing my shirt again and glanced twice, I couldn't believe she wasn't wearing a bra! Plus, she wasn't even wearing pants, her underwear was fully visible! That's a bit too much exposure! I was shocked yet aroused. Noticing the change in my lower half, my sister started to fidget nervously... Although we hadn't felt any sexual attraction towards each other before, the atmosphere suddenly turned erotic, and we ended up crossing that forbidden line!
