Rath in reddit actually posted some estimated numbers based on various testings he did for both Hijikata and Chacha and knowing well how calculations work for this game. Here's the link:
https://www.reddit.com/r/grandorder/...rious_maidens/
As I've said, it's an estimation, though looking at them they do feel accurate to what I experienced, at least with Chacha. Haven't tried Hijikata enough to judge it.