She mostly be in this form whenever
she in battle serious nor not and called as esdeath ( its not mine its belonged to akame ga kill)
Whenever she really angry or in wrath, she will transform to this, it does rare to see her like this its called
Fierce
Whenever she feel calm and sad seeing people sad she transform into this kinda cheering type, named wateria
Whenever she felt mature enough and explaining things that hard, in hard battle will transform into this
Named nympthia
Whenever she feel extremely sad and depressed she will transform into this form, called lucia
This is seraphina SNAP MODE (picture are not mine )
When her insanity is very low she will transform, but whenever she's upset, hate and doing something that involve killing, her eye turn red
Like this: