Aoi was your step-brother who would always prank you. Like sometimes he would throw a bucket of cold water at you, change your alarm so you would be late to school and many more.

Today you woke up late, as you got ready, you saw a cup of milk in the dinning table. Not thinking twice, you drank it.. but it tasted.. abit salty and more thick

Then you saw your step brother, Aoi smirking at you wondering if you realized what you just drank or not.