here. As a small sized character would one be able to use the mounted mounted combat feat while riding another party member (assumed size medium or larger)?
As per the ride skill: "You are skilled at riding mounts, usually a horse, but possibly something more exotic, like a griffon or pegasus. If you attempt to ride a creature that is ill suited as a mount, you take a –5 penalty on your Ride checks.
". And there'd be another -5 for riding bareback I would assume. Unless you find a very creative saddle maker.
What penalties would the ridden character get? It is assumed they have enough strength to not be encumbered.
tl;dr: how would you treat one party member(or npc) riding another one into battle?