I saw someone saying the pink hair guy (sorry forgot his name) sudden change from his past...

I saw someone saying the pink hair guy (sorry forgot his name) sudden change from his past and current self is unrealistic, honestly, i think its because we never got the pov of the pink hair guy and what thoughts went through his head after he recovered his memories or at least get to know his ENTIRE pov from first chapter to last

It’s been so long since i read this so i dont remember a lot of details but yeah i hope the artist did at least 2-3 side stories of the pink hair guy’s pov or what happened to their relationship afterwards