I take NO credit for the original UTAU UST, song, tuning, or the vocals themselves.
I was just testing things out. :P

Main vocals - BF FNF Original voicebank.
Harmonies - BF FNF Power voicebank.

Tools used:
UST WAVE: https://soundcloud.com/uchiha-irene/utau-wave-haato-ust (Download is in description.)
FNF UTAUs: https://github.com/GenoX-Fome/funkin-utau
Tool 1 (append) - moresampler: https://cocoacacao.wixsite.com/cocoa/moresampler-archive (Faster rendering.)
Tool 2 (resample) - TIPS: http://scientistb.web.fc2.com/program/ (Cleaner vocals.)