Third person POV\
[1 week later…]
One early morning at 6:20 a.m., Shu was now finished making something in his own, separate lab. Gen was busy researching for the cure in a separate lab. Shu had made a serum and replicated it with his Template Serum, which can replicate any liquid serum. The lab was dark, saved for 2 desk lamps used for his experiments and reading his notes, and the windows were blocked with grey curtains. He made the serum, which he had called Almost to the Brink of Death. True to its name, that serum didn't allow him to die in any way. The recipe and formula for it are kept as a secret by him in his spiral-bound notebook.
"Ya está hecho..." he muttered to himself while wiping the beads of sweat from his temple, "…es ara fach..."
These lines meant "it's now done" in Spanish and the strange, southern French language Occitan.
He had been up since 5 a.m. for the past 7 days, doing his experiment works from 5 to 7 a.m. and then stepping into his lab at 5 p.m. after his daytime duties. For the past 1 week, he had tested his previous batches of the nerve-freezing serum on lab rats. He injected his batches into them and then stabbed them with a dagger to test the batches' efficacy. He remembered that at least sent 3 of them to death and 2 survived. The last two lived to see the day while the dead three had been buried at the headquarters' courtyard under a Momiji (Japanese Maple) tree, which showed off its brilliant autumn leaves for this season.
So, after that, Shu wanted to test it out by injecting it into himself and find a deadly situation to die in to test its effectiveness and efficacy. These were driven by his desire to cleanse himself psychologically of his sins. "I will be fine…" he whispered to himself with a slight Spanish cadence.
So, as a Roman Catholic (though he started to drop prayers to Mary and the saints from his prayers, becoming a bit more like Protestant), he did the sign of the cross before injecting the freezing serum into his mouth. Gen doesn't know what he was doing now. After that, Shu grabbed his spiral-bound notebook and read an entry that compares his dread with that of Kirito Kirigaya after Eugeo died.
It said:
"I still remembered how Kirito look after his amigo Eugeo died. Those hollow eyes…Yeah, sí, I admitted I looked like him, yet I did not let my dread and depression consume me. I had my own goals for this outbreak.
I was quite mysterious when I made a million distinctions on the psychology of my own mind, like a Calvinist or a Lutheran doing scholastic theology."
After that and a hearty breakfast, he wore his red and grey camouflage gear of Gen's organization and went out to find a deadly situation to die in to test the serum's effectiveness, going with a squad led by Nato. Nato never questioned why he suddenly decided to join in. Mara and Martha, armed with baseball bats and crossbows for clearing zombie hordes, are with them.