Author's P.O.V.:
Bill's world shattered, literally, as he saw the body of his soulmate lying on the floor, drowning in her own blood, a silver knife embedded deep in her chest. He crashed to his knees, frozen and unable to move. This was the second time he has felt this feeling.
The feeling of helplessness, hopelessness, pain, sorrow, guilt, fear, devastation, horror, all feelings hit him at once. He couldn't move, couldn't speak, his body just won't listen to him.
He couldn't handle this, he destroyed his own world but managed to get through it, but now that he lost you too, something that he was fully devoted to, someone he looked up to, someone who he could trust without a second thought, someone who loved him and him only, someone who he loved, he didn't knew what to do. You were literally his everything.
"Aww, what's wrong? Poor Billy boy, why are you crying? Feeling sad? You should feel sad, such a nice girl she was, feisty, but nice" Tad spoke. A huge wave of anger, sorrow and regret washed over Bill as he heard the voice of his ex- bestfriend.
"W-why? Why did you do this Tad? Why?" Bill asked him, looking up at the blue demon.
"Oh stop pretending like you don't know, stop pretending like you care because I know you don't" Tad hissed at the man kneeling in front of him.
Bill only looked up at Tad with lost, sad eyes.
"Ugh... You killed everyone, you destroyed your own dimension, family, friends and didn't even bat an eyelash about it. And now, all of sudden, you care, huh? HUH!?!" Tad yelled, tears going down his own eye.
"You killed her" Bill whispered looking down. "You killed her" he said a bit louder. He looked at his hands then raised his head, flames burning in them.
"You killed her, you mofo! You f***ing killed my soulmate!!!" Bill stood up angrily. Tad was scared on seeing the murderous, insane look in his eye.
"Well, you did kill my soulmate and my family too!" Tad didn't knew where he got the sudden confidence from, but he was glad for it.
"I didn't do it on purpose! I wasn't in control of myself! And I have regretted that ever since! (Y/n), My Angel! She was the only one that made me want to stay alive! I only came back for her! She was all I have! And you took her away from me" Bill was angry, tears were cascading down his cheeks.
"Oh f*** off. You took my everything away from me! And its time to pay for your deeds!" Tad said turning into his square form and increasing his size and changing his dimensions. He became a cube with twelve hands and legs. His eye being big and completely empty and black. His body being a dark blue. His hat was tattered too, just his bowtie was normal. Multiple mouths were there on his face, all with tongues out and dripping black saliva.
Bill, in return, turned to his triangular form. Multiple pyramids lined up, all with deadly red, orange and yellow. His eyes were black, but much more black, like a black hole with black tears dripping down. He had total ten hands and ten legs. His mouths were present on the lower pyramids, dripping blood and being sickly yellow. His hat was there, but it was fine, unlike his bowtie which also had a mouth lined with rows of sharp teeth.
Both demons roared and began fighting.... Wrestling fighting. The two pairs of twins peeked in and saw what was going on. Dipper spotted the (h/c) female. He and Mabel silently creeped up to her, avoiding the dream demons. As Dipper got close, he saw what state you were in. Tears filled his and Mabel's eyes. Mabel began bawling her eyes out. Dipper shushed her, trying to stay strong, he carefully took your vulnerable form in his arms and ran to the exit with Mabel in tow. As the twins met the older twins, they broke down, holding you tightly, Dipper and Mabel sobbed. Stan and Ford, both stood there, with tears going down their cheeks. You, an innocent girl that brought smile to everyone, that anyone can look up to, that everyone trusted their secrets with, got in such a big mess and ended up dying. Stan and Ford hugged each other, wailing silently. Dipper held you close to him, your body already becoming cold and your skin turning pale due to loss of blood. Yet, you looked so serene and calm, as if you were pleased and happy. Mabel hugged Dipper and sobbed in his shirt. Their precious little baby sister was dead, and they couldn't do anything to save her.
"I am so sorry sis, I couldn't protect you" Dipper spoke. "But, I always loved you and always will, we all did, please forgive us" he finished.
"Sis, I'll always cherish the time we had together, I hope you'll be happy in heaven.... Without us" Mabel sniffed and sobbed.
"Oh dear, kid, you were such a sweet and cute baby, you even made my heart melt, something that wasn't easy. I never said it, but I cared for you and loved you, I'm sorry" Stan wailed.
"I have never known you for long child, but the short time I spend with you, I knew you were kind and sweet. I'm so sorry I was never able to spend any time with you. " Ford let some tears escape his eyes "please say hi to (father's name) and (mother's name) from me" he finished, crying.
"Why did you do this Tad?" Bill asked as he threw fireballs at Tad.
"For revenge!" Tad deflected the attack.
"Why?" Bill asked, stopping.
"You killed everyone!" Tad threw fireballs at Bill. But Bill didn't dodge, he just took them.
"I'm sorry" he said after a pause, trying hard not to let his voice break.
"What?" Tad asked, surprised as he stopped his advances.
"I am sorry Tad, pal, I never meant to do that, and I still regret it. You're right, I deserve it, the pain, the sorrow. I don't deserve to be loved, I am worthless" Bill said, black tears slipping down his eyes. Tad paused. Bill looked up as Tad eyes him warily. Bill slowly stepped closer.
"I am sorry Tad, for everything, for every prank, for every tear, for very drop of blood I have shed. But please, understand, I wasn't in control of want I was doing. I was enraged, I couldn't even think straight. I'm sorry for all the pain I caused you" Bill hugged Tad, who was frozen, unable to process just happened. H-he just apologized to me.... Tad thought, amazed.
"I deserved the pain, but Tad" Bills voice turned demonic, "(̵̛̖̲̌͂͊Ỹ̴͈̇̓̐̕/̸̻̼̥͕̟̔̆̾̐͂n̵͕͊̉̈́͆͛)̸̣̩̙̑̈́ ̸̤͇̈́̀̓̉̀ͅͅḏ̴͎͒́î̴̖͒͐ḓ̷̙͗̽͘ņ̵̟̗͕̃̌̎̚'̵̙͉̠͉͕͛̊̽̈́̊t̷̛͓" Bill finished as Tad felt a sharp pain in his lower body. He looked down to see that Bill had impaled him with a demon slayer knife. Blood dripped down from all his mouths as he looked down, then looked up at Bill.
"Guess I deserved it, I'm sorry pal, but even though after all this, I just realized I missed you, and..... I love you brother" Tad finished with an empty laugh as his body turned to dust and disintegrated into nothing. Bill just stood there, shocked, more tears fell form his eyes. He just lost everything, every single thing, even his best friend that he considered as brother all because he was a demon.
*Flashback*
"I told you it was a bad idea!" A young Tad yelled as he ran alongside with Bill, who just laughed.
"But it was worth it, and you agree too!" Bill said.
"I know, but run, if they caught us, who knows what they will do" Tad said running faster, laughing.
"Hey wait for me!" Bill yelled laughing and running behind, half of their demon village hot on their tail.
----
"Are we safe?" Tad asked.
"I guess so" Bill said peeking out, then coming back inside their bunker. They looked at each other and high fived.
"Bro! That was hilarious!" Tad laughed.
"I know right! I told you it'd be fun" Bill laughed.
"Let's do it again sometime" Tad said.
"Sure" Bill grinned.
___________
Tad blushed as he brought his soulmate over to the dining table.
"What does this lovely couple wish to have for dinner?" Bill spoke in a british accent, he bowed, his hand holding a towel, and other holding a notebook, and more hand was holding a pen. Tad blushed more as Sleek, his soulmate laughed.
"Hell! Bill you look absolutely hilarious" She laughed. Soon, the trio began laughing together as Bill made weird faces and noises. As for Tad's dinner date, they all went to prank the others and turned it into a prank date.
*Flashback End*
Distressed and resentful, Bill let out a scream as he crumbled, literally and tears fell out of his eye that was on the floor.
"Bill!" Mabel called out, still crying. Bill noticed your body and he became normal triangle like before. He literally crawled over to her, still crying, his eyes bloodshot. He reached out for you as he looked at you, unable to look away for even a second, turning human, he took you from Dipper and hugged you tightly, sobbing, whispering to himself about all his crimes. He didn't care how broken he looked, because that was what he was, a broken ragdoll, which had no home to go to, not anymore.
He didn't care anymore, no one did. Not even when the cube disappeared and the town went to normal. Not even when they were teleported in the woods near the shack.
All they did was mourn, mourn over the loss of a dear family member, who was a particular demon's everything.
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Such a downer chapter. Its the end though. I feel so bad. Poor Bill, he lost everything. What will he do now? Nothing except for sulking, going mad in his own sadness and loneliness, wishing to die but not being able to kill himself because of being immortal. Kinda pathetic.
Anyhow, the story is complete, I feel bad for my boy.
Edit: guys, stop being mad at me, there are still two parts left, one being chapter and the other is the epilogue, so please stop being angry alright.