Ater rereading the manga I came across the bug that went inside Kafka and that took control over his body against Isao and that made me wonder how is he going to be... Is he perhaps more akin to Sukuna, someone who wants to take over the host's body for his own benefit? Or is it more akin to Kurama, someone who isn't in line with the MC but later on he turns into a good guy?
This might be a hot take but he might actually be a good Kaiju who despises his brothers. This idea comes from the fact that when he appeared inside Kafka he said "Kaiju.. kill" which implies; kill the Kaiju (unless you believe that he was talking in 3rd person which would mean "(I, the) Kaiju... Kill"). Kafka didn't defend himself, he didn't try to fight against Isao which might have triggered our small friend because he was facing something that emitted a Kaiju-ish aura which made the worm think that he was going to die if he allowed Kafka to do as he wished. Another thing to support this is how Kafka is able to freely use his powers. In Yuji's case, he can switch with Sukuna but that makes him unable to control his body whatsoever. And in Naruto's case before he befriended him, wasn't able to use Kurama's power at all unless he lost control. What do y'all think? Would've liked to make this post a thread but I couldn't find anywhere to post it because we lack a Kaiju #8 section lol.
