I used to run quite a few Instagram accounts, mostly lifestyle / product related, with a lot of shared accounts followed and following. Years ago.
I came across EVB because I noticed that she would follow an account, wait a bit, unfollow. First time I assumed she didn’t like the content. Then it happened with each of the others, and I figured that she had a bot working her account - following to get noticed, pick up a reciprocal follow, and then unfollowing. Unfortunately it was v obvious.