toritaten
A "nen beast" created when Knuckle Bine's Potclean transforms.
It looks like a purple cat with a pair or red wings and the hiragana と ("to") on its forehead.
Its ability is to latch onto its victim and force them into the "zetsu" state, preventing them from using nen (hunter x hunter).
Called I.R.S. (Individual Ren Suppressor) in the English translation.