With the recent tragedies occurred all they could think of at the moment was seeing Zerom and trying to convince him that it wasn't their fault and they didn't plan on anything like that to happen. And they get to his cell and they immediately saw Sid guarding his cell and they try to persuade him that he's honestly not a bad person and he even promised not to do anything but Sid felt trust and compassion in their voices so he decided.
"I was never the kind of man to let people convince me but I'm a different man now" Sid said.
"You can talk to him and nothing more." He said while stepping aside.
Tsubaki sprints towards the steel door and got a look through the door and saw him sobbing in the corner with blood pouring out of his body while still wrapped around in the chains and the two spears lodge within his shoulders. The sight even made Tsubaki's heart ache even more than before and before she could speak a word whispers came through the cell.
"You promised…my only friends" Zerom whimpered faintly.
Zerom continues to repeat those words over and over. Tsubaki stunned and unable to speak she just stands there while tears start to appear in her eyes as she slowly starts to walk away and shuts the prison door and then she suddenly collapses and breaks down in absolute sorrow and her friends try to comfort her and says that he isn't going to be killed and Tsubaki looks up and says
"I know but I promised him."
They once again head to Death's room where they try to convince him once more but when they get there Lord Death is there and so is Zerom. Overwhelmed with relief and happiness Tsubaki reaches for his hand while saying his name to pull him into a hug but when she touches his fingertips Zerom moves away from her touch.
"You promised." He said in disapproval
With such shatter of happiness Tsubaki is frozen and just whispers in such loss in her voice
"…Zerom"
And with that she also realizes a giant contraption of metal that appears to be a cannon is mounted right next to Death and as soon as she sees it she knows immediately what it is and what's its purpose is and then her mouth opens up and words just manage to escape her lips
"…No"
Tsubaki knew what that massive machine was and why Zerom is there and the conclusion makes her drop to her knees because she knew that this machine was going to be the death of Zerom and also knowing what Death was about to do.
"It must be done" Death proclaimed.
Then he starts to charge up the cannon and without missing a heart beat Tsubaki runs and shields Zerom from the cannon and it was obvious that she wasn't going any were. Lord Death shouts to get out of the way and that the machine can't be stopped when it's active but Tsubaki just stares down at the barrel of the colossal cannon and then it fires.
Everybody tries to chase towards Tsubaki but it's too late and everybody was do shocked it seemed everything happened in slow-motion and then in a flash the beam strikes leaving a whole behind. Steams starts to arise from the whole and Tsubaki slowly opens her eyes and shocked beyond compression to see a whole not in her chest but a whole in Zerom's chest but yet she is still confused by the terrible sight and realizes just in the last moment he shielded he from the blast. But even Lord Death is shocked at the scene but then Zerom just turns around and mumbles
"You promised…but you're my friend"
With the words bringing Tsubaki to tears Zerom falls by her side with blood gushing beneath Zerom. With the silence filling the room Tsubaki turns around and collapses on top of Zerom screaming and weeping while the rest of them surrounded her and Tsubaki continues to scream
"Zerom! Don't Die!"
But with Zerom fading more and more unconscious he can only think to himself.
"…don't cry…Tsubaki" He pleads.
Then it happens.