One night, I thought my super serious sister came home drunk and came to my room to spout dirty jokes! She took off her clothes and showed her underwear! She pressed her breasts against me, took off her pants, and went on an obscene erotic rampage! I had no choice but to let her sleep in my bed... When I woke up in the morning, she seemed to have no memory at all! Why!? Naked!? And she was fidgeting and blushing in embarrassment, which was so cute that I involuntarily got an erection! And then, noticing my erection, she got excited and we ended up having sex...
