Teke Teke is a malevolent Japanese ghost / demon that has entered the domain of both Urban Legend and horror franchise in its own right : similar to the more infamous "Slit Mouth Woman".
Teke Teke is named after the sound the monster makes as it pursues victims, "running" across the ground using her hands as her entire lower section has been torn off, leaving nothing but her upper torso and arms by which the demon hunts down her prey.
Originally human, the woman who would become Teke Teke was involved in a horrific train accident in which she was literally cut in two and now her vengeful spirit stalks the streets of Japan and upon spotting any living being nearby will pursue them, armed with either a saw or a scythe - which she uses to slice a victim in two, mimicking her own demise.
Teke Teke belongs to a very large subtype of Japanese demon known as the "vengeful ghost", usually women these demons were once human but became monsters after death and now exist to kill and torment the living.