So, this is purely speculation, but I'd guess this skill, Run from Regret, comes from dying to the unforgiven hands many times without a containment suit and adding to its smoke A LOT.
Why? I suspect there's some kind of running HP total for the unforgiven hands that carries over from battle to battle. I dealt it 40 damage with a containment suit, and then 80+ damage in one go with a containment suit, and I died both times from its end-of-round effect. Next round, I stalled for two rounds and then did exactly 19 etheric damage and it died and I got chains of regret. So feeding it a lot might actually result in another resolution.
Second theory- it involves running away from the hands a bunch, but it must be a lot of running, because I didn't get the skill from constantly fleeing this thing while trying to do other things in the church.
Third theory, and now that I think about it, most likely- Failing to run away from the hands and dying to its normal attacks. That would probably make the most sense, thematically, and it even has a tight hold attack (I'm not sure which one) to facilitate this!