Rin was thrown back from Amaimon with tremendous force. Yukio struggled against the goblins that pinned him against a tree while he could only watch as his brother is thrown around like a toy.
"What the hell do you want, Amaimon? I've taken care of you before and I'll do it again!" The half-demon spat blood from his mouth as he gripped Kurikara even harder.
"I have a job to do now. Before I was just playing. You haven't seen my strength." A pillar of Earth flew up from underneath Rin, throwing him straight up in the air. The sword was knocked from his hand and Amaimon rushed to get it.
"Rin!" Yukio yelled to his brother in panic. The goblins tightened their hold.
"Don't try to stop me. It's only a matter of time." Amaimon slammed the sword hilt deep into the soil as Rin fell to the ground. The boy struggled to his feet and rushed toward the Earth King.
"Hey! What're you trying to—" His words were cut off as the demon snapped the hilt off the blade. The flames that surrounded the sword flew back to Rin. His body convulsed as the power flew into him and he let out an unearthly scream.
"Well, this is more interesting than Father said it would be. I look forward to see what else is in store." The demon seemed unfazed by the torture that his half-brother was going through. The screams continued as he became more and more demon like. His teeth became more like fangs, his nails became claws, and his eyes became a dull red.
"R-Rin?" The younger twin hesitantly called to the older. The boy turned at his name and walked toward the tree where Yukio was being held. As he went on, it was clear something was wrong. He didn't actually walk—he half-walked, half-stumbled over to his brother. He stopped about a foot away and looked back at Amaimon.
"I see now. You want to leave your mark. Go ahead, just don't kill him." Rin turned back to Yukio after hearing what Amaimon had to say. He swung his arm back and brought it down across his brother's body.