If Darres is handy with any sort of a weapon, they can totally bond over sparring. And yay, more military CR! That's where Chrom feels the most comfortable for sure.

He'll offer a hand of friendship to Zelman, but if he's rude, he'll just go 'eh' and leave him be. But if Zelman actually causes trouble or hurts people, 'eh' will definitely turn to 'EAT SWORD.'