Thinking about reaching such a level, one would probably need to render their entire will into nihilism, which isn't much different from death.
If Su Yu's Nihility Walker were at full level, and he unlocked the Core Specialization, he might be able to reach that state while retaining his will, but now he's still some distance away from full level, completely unable to do it.
Therefore, Su Yu still needs to maintain the time and space he is in, in order to sustain his existence.
"Su Yu, stop resisting! You're bound to die today, so why not accept it calmly..."
Qi Chen's sinister voice came again, once more adopting a tone that suggested everything was under control.
Hearing this, Su Yu turned his head to look around but still couldn't see any sign of Qi Chen. Then he smiled nonchalantly: "Fine!"
Having said that, Su Yu kept his word and astonishingly withdrew his defenses, allowing Qi Chen's [Death], the data collapse space black hole, to swallow him whole.
