At the moment I can't think of anything that's straight up mercy except releasing girls untouched (or maybe releasing them non pregnant after getting a few minions out of them

), and even then they're rude about it if you just haven't brought them to the lair yet.
And nah, I can throw fights twice per day/stamina, and for each throw infamy goes down by a minimum of 5 at my current lvl.
Since it takes half the current health you can only do it 5 times without getting healed.
So that's at least 25 infamy less in an awake period if that's all you do.
How about 3 per month, or if you have done nothing to raise your infamy by x days you lose a point or two?
With maybe a cap so you won't be encouraged to sleep the days away if you have enough sat and coins.