During summer vacation, my little sister brought her friend home, but the air conditioner in the room was broken, so it was like a hothouse steam bath! The fan didn't cool her down at all, and she was covered in sweat, so in an effort to cool down, she lifted her skirt in front of the fan and blew air on her, exposing her panties and nipples one after another! Of course, that wasn't enough to cool her down, so she eventually took off her clothes and bra, leaving her in just a camisole! Seeing her defenseless and overly erotic state, her brother became aroused by his younger, immature body...