(Yuya may seem to have a split personality. In actuality , I forgot to mention it's his darkness that lives in his soul room. I am not insulting in any way of this mental disorder just to let all of you know so don't take this seriously). Also this story will be pg to pg-13. No excessive gore or violence details or bad language. Just implied or not.
Bold-Zarc(yuya's second personality and brother) speaking
Normal-Yuya speaking
Italics-Duel Monsters speaking(any of them but mainly timegazer and stargazer magician)
Underline-communicating in mind links
Sakaki Yuya have lost count on how long the inter-dimensional war happened. His friends and allies have fallen before him. He can't recall how many times he entered in his Berserk mode against his enemies. All the four dimension are already on the verge of destruction. So much pain, grief, and misery is almost enough to send the poor boy's mind insane. His darkness in his heart continues to grow. However it has been misunderstood, the darkness only wanted to protect Yuya from fatal danger. Zarc [Yuya's darkness] manifested as his second violent, overprotective personality. He claims Yuya is part of his alter ego, was locked in Yuya's heart because the other Yu boys revived him accidently but was defeated by Ray. It was then they both realized Zarc went crazy because of his dragons' anger and his obsession of dueling. The results were their souls are intertwined until the next reincarnation. Yuya would not recover the memories but Zarc would have all of them. Zarc could materialize(in ghost figure) so only Yuya can see. His hair would stand, golden eyes shine brightly, would kill anyone if they threaten or insult Yuya. Both cleared any of their past problems and somewhat became as brothers (in mind).
Yuya (& Zarc) is currently in the Fusion dimension. His deck is mostly covered in ash or dust. He could sense his duel monsters' emotions are sadden by his situation. His smiles and laughs are becoming deranged and fake as days goes. One night, Zarc (they switched control) found rubble of rocks along with woods to sleep upon. They both stared up, looking at the starry sky.
"Dragon(Zarc), do you ever wonder if I were to somehow change ways like becoming stronger and smarter to prevent important things ever taken away from me," ask Yuya aloud.
Zarc replied through his mind,"I'm not sure, no matter how powerful or intelligent you wish to become, you can't protect everyone, King. We are not gods."
Yuya realized that but wants to denies that's not true. He starts to sob uncontrollably as Zarc is comforting him by partially controlling his(their) arms to hug around his body. Dragon continues to soothe his King with small words of encouragement. After several minutes, Yuya calmed down and Ichigo unwrapped his arms from their body.
"Thank you, Zarc. You have been so kind and helpful along with my duel monsters and m-my Nakama," softly spoke Yuya. He could feel his face flushed as his lips moved on its own, Zarc replied,"Your welcome. After all, I'm your older twin brother to protect my little twin brother." Yuya's mindset is messed up by the war, so he accepts that his other personality is his brother because he never wants to be alone. Also, he is an only child, no siblings. They both can hear, read their minds and feel their own emotions to some extent. Unknowingly, the pendulum pendant begins to swing ever so slightly from their neck.