You stood next to Undyne, a sword in your hand and determination in your heart. Asriel was powerful, but now refused to fight. And another war between monsters and humans had begun. Calling him to the field as a peacemaker, therefore you as his guard. A training bot made by Alphys waited to fight. Undyne began your training.
"You do it for him,
And you would do it again.
You do it for her, that is to say
You'll do it for him."
I nodded and followed her instructions.
"Keep your stance wide,
Keep your body lowered,
As you're moving forward
Balance is the key!
Right foot."
I stepped as she did.
"Left foot,
Now go even faster
And as you're moving backwards
Keep your eyes on me."
I was catching on, smiling at the bot.
"Keep my stance wide."
"Good."
"Keep my body lowered."
"Right." She nodded.
"As I'm moving forward..."
I faltered, stepping sideways and losing my balance. Undyne pulled me up and thruster my sword at me.
"Concentrate! Don't you want him to live!?"
"Right foot; left foot."
"Yes, but put your whole body into it!
Everything you have, everything you are
You've got to give,
On the battlefield."
She looked at the picture of Alphys, in the wall. Undyne was a soldier, but she was able to teach me for a while. Alphys was still there, still hurt.
"When everything is chaos,
And you have nothing but the way you feel, your strategy and a sword.
You just think about the life you'll have together after the war!"
She stood, smiling at me.
"And then you do it for her,
That's how you know you can win!
You do it for her, that is to say
You'll do it for him."
We started again, activating the robot.
"Deep down you know
You weren't built for fighting,
But that doesn't mean
You're not prepared to try."
I swung at the countering weapon.
"What they don't know
Is your real advantage,
When you live for someone
You're prepared to die."
"Deep down I know
That I'm just a human."
"True."
"But I know that I can draw my sword and fight!"
"But you know that you can draw your sword and fight."
"With my short existence," I faked a jump, and tripped the robot.
"Good."
"I can make a difference," I moved at its neck.
"Yes, excellent!"
"I can be there for him,
I can be his knight!
I can do it for him,"
"You do it for her."
"Okay, now do that again."
"Yes, sir!" I sliced at the robot and finished it off.
"You do it for her, and now you say:"
"I'll do it for him." I finished, spinning. And there, standing in the distance, crying softly with a sad smile, was Asriel.
"You...you'd fight...for me?"
"Of course, Asriel. You're important, to the world and me. You must carry on your parents legacy, keeping peace in this world."
He ran at me, giving me a hug.
"Just don't...get hurt, or die, okay?"
I stopped smiling then, glancing at a nervous Undyne.
I have broken that promise, as I lay here bleeding.
And his cries have caused the truce we needed.