From Bitter Root Wiki

The Kantoo are rabbit-like creatures that originate from Barzakh. The Kantoo were brought to Earth by Enoch Sangerye after he opened a Gateway searching for Nora Sangerye after the Red Summer. The Kantoo are small and red and can detect the presence of the Jinoo.

Enoch was particularly fond of the Jinoo and used them to protect his house, referring to them as his "guard dogs". They would later play a large part of the Sangerye family's battle against the Inzondo given they do not react to Inzondo but do to Jinoo — this allowed the Sangerye family to make distinctions between the two given their similarities.

Later, the Kantoo would prove to be more useful, and proved that by pollinating the trees ravaging Harlem, they could force them to retreat, but not defeat them. This allowed the Sangerye's to combat the trees whilst also combatting the Inzondo.