I'm writing a short fantasy story in 1st person view about a male and female protagonist becoming allies and having to chant spells to save a city, currently I'm considering having both protagonists swap narration in each chapter.
I ask this because before the end of chapter 6 (out of 8), the female dies a shocking death, so the male had to take her place, therefore he gets to narrate throughout the rest of the story.
Yet at the same time, the male doesn't speak much but has a lot of internal monologue, so I might be able to use up to 4 short chapters for him (compared to female, her chapters are longer). But I've never included more than 1 narrator before, is it necessary to balance both narrations in terms of the length of each chapter?

Currently it is assigned like this:
Chapter 1: Female narrator
Chapter 2: Male
Chapter 3: Female
Chapter 4: Male
Chapter 5: Female
Chapter 6: Female
Chapter 7: Male
Chapter 8: Male

It is your book, do what you want.