>>2392879He can be absolutely brutal towards his enemies; there are several conversations that suggest that once you've gotten on his bad side, he just doesn't give a fuck anymore. In this aspect he resembles Squall - he kills whatever needs to be killed and won't lose any sleep over their fate, no matter how terrible it is.
His loved ones are a different story. One needs thick skin to endure his bantz and jabs, but beneath the indifferent surface he's deeply compassionate and thoughtful, probably more than anyone in the group. There's a convo with Cor where Noctis admits he'd rather fight the whole war alone to spare his group from danger.
TL;DR: He's too multifaceted for the fanfic writers.