MIAA-609 I've taken my girlfriend's sister's teasing seriously.

When my girlfriend was waiting in the living room for a date, her sister came back in the morning wearing a bold dress that almost looked at her underwear, which made people wonder where to look, and then she suddenly made me flirt, and my girlfriend was so important, but the temptation for a slutty sister to do that was unbearable, sneaky mouthing, a night attack, and an even more intense flirting, and I was so nervous and I finally, although I was discovered by my girlfriend, it didn't matter to get out of control.