Originally Posted by Skyehmm

Yellow girls (or Pierce type)

http://harem-battle.club/wiki/Flower...Beast-DEF-Ampy

Good on you for answering the question accurately, but people should be actively discouraged from caring about the answer. It's truly a waste to assign ampys to girls based on the XP they give...that's not their primary function and we get more than enough lvl 5 manyus that give exactly the same XP in exactly the same conditions.