Every time i get into combat with any monster and the name turns red, I realise that there would be a boxed alphabet/letter that goes in sequence from a-z.

Let's say the current target I am fighting has a label 'j' next to the name (on the right), then the next target I engage, no matter the type, will have a 'k' on the right of it's name. What exactly is this sequential alphabets for? Besides making alphabet soup out of all the monsters I kill, that is.

Thanks!