Ukon can only perform this technique after activating his cursed seal's second level. Using his chakra, he disassembles his body on a cellular and proteinic level so that he can enter a target's body. He then starts reforming himself, taking over certain parts of their body and gradually corroding the parts he hasn't entered yet. Ultimately, the target dies, achieving this technique's primary purpose: assassination. Ukon had previously been very successful in this regard, as the only way that victims could stop him would be by attacking their own bodies, something that none were willing to do. Kiba Inuzuka, however, experiences no such unwillingness; he badly injures himself, doing the same damage to Ukon, and in trying to kill himself drives Ukon from his body so that Ukon will not suffer the same fate.