@EdgeOErin in the user guide is this bit about Groups. Looks like a Pro acxount is beeded to participate.
Alternatively - using the hashtag #booklovers and other tags associated with a love of reading is sure to find other like minded folks, for example #opencarryBooks is one.
Here is a link to the user guide, https://help.counter.social/en/latest/pro-features.html#coso-groups and this snipped image is all I found on groups.
Search the hashtags and pin them in a column for easy following.