Arguably one of the earliest consumer use cases that found footing was AI girlfriend/boyfriend. Large amounts of revenue spread across many small players are generated here but it's glossed over due to the category.
Given that how widespread romance scam schemes already are (the "market" is at least $0.5 billion/year), I would expect any reasonably functioning AI girlfriend/boyfriend model to be massively (ab)used also against unwilling/unwitting "partners".
I think one related area we'll start seeing more of in the future is "resurrected" companions. You have a terminally ill family member, so you train a model on a bunch of video recordings of them, then you can talk to "them" after they've shuffled off this mortal coil.