It's just easier for me to link this here, another EC, this time from Date-A-Live. The trigger is seeing a loved one hurt and relying on a dark spirit/power within. It also looks like it will play a part in the next season. It's undone by a kiss though not too long after.
http://charmed.forumotion.com/t333-date-a-live-ec
Also, a bonus for this site, it looks like the main character's little sister Kotori might undergo a EC as well. According to TVTropes at least. But here's her little wiki
http://date-a-live.wikia.com/wiki/Kotori_Itsuka
Tohka before and after.