The Ghost of Him
In that pocket dimension of their shared eyes, Obito and Kakashi clash, kunai against kunai.
Blood splatter as Obito's reach digs deep. "You're getting weak, Kakashi," he sneers, because these past decades do no favour for his grudge against Kakashi's endless wins during their adolescent years. "Not so strong anymore, are you?"
Kakashi glares resolutely back, but internally it's a different story. He subtly laughs a pitiful sound to himself because he knows he's already lost, and that's a firm fact Kakashi doesn't begin to doubt.
His reactions are too slow, and his consciousness of Obito's attacks too lacking. But it's not his fault; it's habit woven into his soul.
He can't see Obito as a threat.
Behind Kakashi's thoughts is the memory of a young Obito, forever the caring boy who changed Kakashi's morals for the better. Forever the boy who died for his sake under falling rocks. Forever the boy who smiled for him in his darkest hour.
Behind Kakashi's every action is a silent salute to Obito. He'd replaced the Rules and Regulations for Obito's nindo. He'd carried Obito's silly excuses to keep the world whimsical and lively. He'd taught Obito's beliefs to keep his legacy alive.
Behind Kakashi's loan eye is the feel of Obito, warm and safe, like a hand grasping his in case he falls a little too deep into the darkness ensnaring his mind. It swirls within him until their identity is one of the same, because Kakashi wouldn't be here if it weren't for Obito, and Obito had once wished to live through him, through his eye, until the end of Kakashi's time.
Obito will always be comfort and home – has been for the last twenty years – and it'll take more than an hour's worth of battle to change his view of that.
Obito won their fight before it even begun.