What is phys_bone_follower?

My map reached entity limits and when increasing more entities, the game crashes of course...
hammer shows up my map using only 1100 entities but when i check my entity number in game, it shows already 1900 of entity is in my map and 900 of them is phys_bone_follower.
i check the my_world (flowey fight map) that contain bunch of entites like my map
and not a single phys_bone_follower in that map so i think that thing is not so important for usual situation?

So question is what is phys_bone_follwer, what it needs for and i want to know why bunch of them generated in my maps

if you need information of my maps,
say to me if it helps to find problems

sorry for bad grammar
i do my best

Crash said:

I'm willing to bet you have a bunch of class model props in your map?

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exactly... i didn't notice that because i just panic
when i search for that in google there's not a single search result for that thing and didn't remember there's hundred of dancing demoman player props in my map... sorry for idiotic question

Crash said:

iirc there's a way to turn off those bones on them. I'm not at my PC right now otherwise I'd look, but check all the options, including the flags.

Click to expand...

there's option for disable bone followers, is there any affection to prop when i using this?