I used double pepper for double the fun, both in difference sizes. But is there a way to choose which of them you use in sex scenes?
Not to my knowledge, no. From what I understand, the size capacity of the NPC dictates the penis which will be used during the scene.
Although, from what I recall most NPC's don't really have size restrictions - I think it's only Etheryn (whom starts out with a 12 inch maximum size restriction - you can stretch her out though, by fucking her [
Monstrously] with a bigger penis then going back to the smaller one and visa versa
according to this post here).
But yeah, I think that the game tries to use the biggest penis by default, then if there are size restrictions it will go to the second penis (assuming it's smaller in size than the other one - unsure of the priority if the penises are the same size (probably #1 first)).
EDIT: With regards to Etheryn though, you can technically choose which penis you use during her scenes - [
Monstrously] (regular sex menu) and [
Ruin her] (ruin her is the first sex scene you get with her after her [
Blue balls]) use a penis that is too big for her, whereas the other scenes use the one she can handle.