Fio Ira

The magical girls are fighting these things called Iras, which are creatures formed from a magical girl who feels extreme anger or other big emotions. However instead of just killing the girl instantly they just hold the girl hostage within them and they hunt after whatever made them feel that emotion or to absorb other magical girls within their ira form. If magical girls are iras or trapped within an ira for more than 2 hours, they are stuck that way permanently. Even when the it’s are defeated the magical girls within them will cease to exist. To combat this, magical girls are gifted essentially pendants or charms based on their anima (soul) and those pendants will trigger a scent, memory, or image of something to calm down a magical girl if she gets too close to forming an ira. They can also glow to show an ira is forming or already formed nearby. 

There’s these beings called Angelus’ who give magical girls these pendants or charms based on them showing extreme courage, strength, integrity, generosity, etc and these pendants allow them to transform and give them magical abilities