I think there may be more then 2 demons in game currently
Considering how demons are created (read
's origin) there could likely be a lot more demons in game then we think.
Fiddlesticks or
Nocturne could've been born of fear and thus feed on it
Shaco could feed on chaos, hence his name
Morgana could feed on anger/rage (but this one is less likely)
Jax could (maybe) feed on attrition (again, not likely but I'll put it here)
Heck, for all we know, demons could come from the void, so
could all be demons.
Idk, maybe there are more, but these are all I could think of for possible demons, I think the first 3 are likely to be demons/are going to become demons when their VGU's come, but we will have to see.
are the same species so you can't have one be a demon without the other.