Ohito, Drulo, and Oppurtoon

These three characters where a little easter egg in the original boiler room art, where there was a hole and the notes was a conversation between them. Whether or not Hitoo will add this in the final game as a joke is unknown.

The names are a blatant mix and match of

Hitoo

Drewrulo

and -Opportunity-

the developers of FNaFB 4, Or Five Nights at FredBears 4

(The names aren't the original as the original conversation was deleted from the boiler room art when Marioguy updated it)