相互フォロー

The Weblio entry defines 相互フォロー as users following each other on a social network, usually arising when one user follows and the followed user follows back. It adds that on services where a request must be approved the relationship is more often called friends. The page gives no date or origin for the word, and none is documented here. In Japanese posts the phrase is often attached to profile lines or requests for follow-backs, but this entry does not rely on a source for that. The English entries mutuals and mutual-bait cover the same idea in English-language social media.