Sadly, for every quality mecha manga like last week's example, there are plenty more like today's selection: one where it is merely an accessory to a lot of nonsense and bad ideas.
KANNAZUKI NO MIKO: DESTINY OF THE SHRINE MAIDEN, by Kaishaku. First published in 2004 and first published in North America in 2008.
PLOT:
Himeko is a passive, insecure young girl who is not only friends with the class idol Chikane, but is secretly admired from afar by the handsome and mysterious Souma. Her quaint life and happy friendship is broken when a strange eclipse lets loose demonic forces and powerful robot suits in order to try and kill her. Himeko is saved by a combination of Chikane's kiss and Souma switching sides and fighting back the demons. Now their fates are tied together by an ancient prophecy where the girls must seal the evil away...if it doesn't tear them apart first.