About a week prior…
The kid brother rifled through Kagome's desk looking for a calculator. He had left his at school and needed one to help him finish his homework. Just as he gave up on his quest, the phone rang so he picked up the cordless handset that stood on the desk. It was a phone call for his mother who had gone to the store.
"May I take a message?"
His hand flipped to a blank page of Kagome's notebook to scribe the note.
A voice from downstairs beckoned for the young boy.
"Coming, Jii-san!" he yelled back lest the patriarch continue to shout. "Ah. Sumimasen, can you repeat that again?" Souta apologized to whoever was on the phone. He continued to jot down details as he sandwiched the phone between his ear and shoulder and trekked downstairs. By the time he entered the kitchen, he bid farewell and hung up. Placing the notebook on the counter next to the stove, he squinted at whatever his grandfather was cooking up in a pan.
A layer of grease floated atop some green liquid, its surface only interrupted by a rehydrated lizard tail and something furry.
"Jii-san, you aren't making dinner are you? Because mama just stepped out to pick up something." Souta took an experimental whiff and reeled back, his eyes watering as he gagged.
"I found a recipe in the shed for a tonic that'll cure baldness! We should give it a try. What's the worst that can happen? I'm already losing my hair! Now continue to stir this while I pour this bottle that I found in the shed with the recipe."
The boy pulled his shirt up to cover his nose and then took the wooden spoon from his grandfather. Souta would have to warn his mother to throw away the tool and the pan when she got home.
"So I'll just slowly pour this in…." the old man tipped the bottle and all seemed to be rather uneventful for the first 2 seconds. Then the pan went up in flames that almost licked the ceiling.
Souta jumped back and dropped the spoon into the pan in alarm, causing flames to splash onto the counter.
"Oh no! Kagome's notebook!"
The cover smoldered for a good 5 seconds before out of nowhere, a tall boy appeared, yelling in anger and pain as he snatched up the book and ran it under cold water.
He seemed to sigh in relief as the flames went out and even took the time to throw a lid over the pan fire before facing the Higurashi men. "No more fires. Kagome is-" and then he just disappeared.