>>531548668
I feel like the TP mechanic is only a thing because Kris is resistant to (Us) and it represents more the "tension" between us and Kris/the Party. Which is why certain seemingly normal ACTs cost TP, likely scaling on how little the party member wants to do them or just how straining it is.
Frisk never had TP since Frisk was basically always trying their best to follow commands, so we didn't need to build up strength to force shit.