Question Regarding Voices or Custom Instruments

[DiamondDoom]

I recently wanted to make a Friday Night Funkin mod that had custom songs. I used this site to make early prototypes of one of the songs, but for Boyfriend's voice, I decided to use the synth bass instrument as a sort of placeholder since it stood out from the other instruments. I wanted to know if it's possible to recreate his voice as an instrument or create a sort of custom instrument using the voice clips so I wouldn't have to add the voice in a separate program. If anyone knows a way to do this, please let me know. Any information is much appreciated!