Summary by Salem
KoMarisa lives in a cardboard box behind the school sports hall, a well hidden place where the stray live safely and might even slips through a total extermination. But KoMarisa and her two younger sisters (Marisa and Reimu) goes against their parents' warning and go on "exploration"
They got caught by children and got toyed with. After being taped and stabbed and flicked and crushed under the table during lessons, Marisa is forced to show where her house is. The children said they're looking for the culprit who destroyed the flower plantings (although in the end there's no proof that Marisa's family is behind it).
The pregnant mother Reimu got kicked, and then the stalk is stabbed to KoReimu whose feet is peeled and attached to the peeled forehead of mother Reimu.
Elder sister Marisa is later stuck into mother Reimu's eye socket and their paste merged into one.
Father Marisa who just came home is put to hang on to the bar (the picture) and later the youngest Marisa is hung to her. Father Marisa holds despite being thrown with stone and stabbed with pine leaves until the children push stone into her body and she fall with KoMarisa. Both survive although weak.
Back at home, father Marisa saw her ruined wife and children. The next day when the children came to visit, father Marisa beg to be killed. But the children just laugh and say the teacher told them to "not kill living being" and that Marisa called herself living being.