Sex scenes

Twilight

 * You need 1+ techs

Applejack

 * You need 5000+ food

Pinkie

 * You need 1+ happiness

Rarity

 * You need 300+ gems

Fluttershy

 * You need 150%(or 200% im unsure) ecoscore
 * Unlocks on Ascension

Rainbow

 * You need 50+ prisms Happens when you Ascend.
 * You have to reach Ascension level 2 to unlock her

Derpy

 * Unlock every other character, which unlocks the ability to hotswap characters, and she will be in the list available to swap to lock everyone else, which unlocks the ability to hotswap between characters, and she will be in the menun