Board Thread:What Would You Do?/@comment-35898511-20180718044425/@comment-29325824-20180724093249

Well, it says so in the Spirit Energy page, and is quoted from one of the books, though I'm not exactly sure which one. I'll check and be back in a bit.

EDIT: Yep, it's from the very first book. Early on, it outright says that that's the biggest difference between male and female SE.