Here I am again.
Spooky Jim, he is Josh's alter identity.
But I think it's more than that. I think spooky Jim is Josh's blurryface.
In some concerts while they were on tour they had Josh battle himself.
I think Josh was really battling spooky jim or his blurryface. In the end he defeats him. Spooky jim gets shot or his head explodes because he was defeated. I think just Josh being on stage means it's how he always feels, alone. It symbolizes that he feels he is battling spooky Jim on his own but he think and knows he can control him.
Of course spooky jim isn't as popular as blurryface because Josh thinks that Tyler's blurryface is much more hard to control. So Josh keeps quiet on how he feels.
But he defeated him so now that's why he's going to be singing more in the new album because he is over coming his fears and anxieties.
Now he has to focus on keeping him away and to help Tyler.