Humans:

Very few humans know of the existence of Irregulars, the majority of them only know of them through myths and legends. Humans are quite prepared to battle Irregulars armed with knowledge from their lore.

There are a few hard-to-access websites and underground stores that specialise in preparing hunters and the parafied for defending against/hunting Irregulars.

Humans have treated Irregulars very badly in the past, so there is a lot of hate towards them.

Roles:

Hunter: humans who hunt down Irregulars to detain or kill them. They may only target Irregulars that attack humans, only target those who choose not to disguise themselves, choose to target every Irregular, etc. Each hunter is different, but they often come together as a community to share information or kill a particular difficult Irregular together. Though there is conflict between people with different views, hunters typically have a begrudging respect for one another. If you're a hunter, there is always a hunter you can go to for help.

Conspirator: used to reference the humans that try to prove the existence of Irregulars to others. The humans may not actually know about Irregulars (i.e. IRL monster hunters), or they might have had some experience with them in the past (i.e. someone who saw a vampire once and is determined to prove they exist)

Paraposer: humans that know of Irregulars and try to pass themselves as an Irregular. This could be sneaking into an Irregular street or telling another Irregular that they too are an Irregular.

Oblivious: humans that don't know of the existence of Irregulars.

Passive: humans that know of the existence of Irregulars and are totally chill with them.

Parified: the humans that are scared stiff of Irregulars. May or may not actually know that they exist.

There might be a few that I add later, so suggest a role or some ideas if you have any.