11/21/13: Was gonna make a full, traditionally colored pg on Rivala's reaction to Lethe's hair, but meh. In many anime/manga, the heroine will typically cut/grow out their hair because:
1. Author wants to show a passage of time
2. Main char has had their heart has broken
I've been thinking of changing Lethe's hair for years. If you look back at the first comic her cut used to be much neater, it's gotten a tad messier but hasn't undergone any major changes. I've never actually colored any scene that shows her before she started dyeing it. I also wanted her to look a bit older. Her bangs sometimes got in the way of showing her facial expressions well.