Raidou's day job - when he's not in school, whenever he goes to school, if he goes to school - involves doing (most of the) legwork for the Narumi Detective Agency. To make this easier, he will frequently use his demons, most of whom have special abilities that help him find clues/get information from whomever he's interrogating. Every demon has at least one investigation skill based on its order (Pyro, Frost, etc.); some have additional skills based on their species.
( Cut for length and minor spoilers )So basically what I need from you is to let me know what Raidou's demons can or cannot do to you. It would also help to know whether they can physically attack you should it come to that, e.g. Gdon attempting to maul Canaan when he injured Raidou. (I am generally fine with campers attacking them, with the understanding that they will retaliate - and if they don't, then Raidou probably will.) Raidou's demons will not attack unless provoked, although Gdon will probably threaten you or be generally rude.
Edit to add: It would also help to know if your characters can see or otherwise sense demons. Most humans in the Devil Summoner-verse cannot, unless they are summoners or otherwise supernaturally gifted (or Victor, but it's anyone's guess what's up with him). The only possible exceptions I can think of are humans trapped in the Dark Realm, which is where most demons normally live, or demons who deliberately reveal themselves to humans, as one does to Raidou and Narumi at a certain point in the game. Raidou's demons do not generally reveal themselves to "normal" humans, and tend to assume you can't see or hear them unless you address them directly, although some of them are getting used to total strangers talking to them in camp (they may not
like it, but they're getting used to it).
Edit again to add: As far as animals go, the canon is a bit sketchier. The stray cats you find in alleys around Tsukudo-cho will not react to a solo demon, although they will startle and run if Raidou approaches them. On the other hand, there is a dog in the second game who reacts warily if you approach him with a solo demon but is perfectly happy when Raidou does the same, whether Raidou happens to have a demon out or not. Whether this means that the dog's demon-sensing skills are more acute than the cats' or that the cats are simply very zen about the whole thing is debatable. For the time being, I am assuming that animals can generally see/sense the demons.