As a young believer I had some yuk demonic experiences and didn't understand it at the time but God taught me some stuff
I have seen demons that look like animals and also different size demons representing a hierarchy.
In one experience a smaller demon I rebuked and defeated went and got a larger demon to attack me.
This larger demon was about 6 foot and the smaller demon about 4 foot
I have also seen fallen angels and they are different to demons and have authority over demons.
One fallen angel appeared to me in a dream and they had demons under their authority - the fallen angel came towards me but the demons were behind it and were afraid of me.
The fallen angel wasn't afraid but very angry with me and spoke to me but it could not get closer than about 7 feet as there was a Holy Spirit barrier between us
Demons have different levels of power but fallen angels have much greater power
I know it sounds crazy (please believe me I'm not crazy
) and in real life I rarely talk about this stuff unless I feel there is a teaching purpose
I have always focused on Jesus and if these things occur then I have to deal with them