S/o loves giving complements to the bros in many ways. "Wow gladdio, that's some nice biceps you got there.."/"ignis, you have really pretty eyes"/"your hair looks really nice today, Prompto!"/"dang Noct, you're so chill to hang with" kind of way? How do you think they would react to these xD
How the bros would react to their S/O complimenting them:
Noctis: Noctis would just sort of play it cool, like “thanks I like hanging out with you too.” But he’d turn away so they wouldn’t see him smiling and he’d feel it like a warmth in his chest afterward.
Ignis: After they complimented his eyes, he’d blink a few times and ask, confused: “My… eyes? Oh, well thank you.” If he was taken off guard he’d adjust his glasses and blush ever so slightly before returning the compliment.
Prompto: He’d grin super wide and not even try to hide his blush. He’d rub his hand on the back of his neck and hair and blow his fringe out of his eyes. “You think so? Thanks!”
Gladio: He’d give a smirk which he knows will drive his S/O mad, looking at his arms like he’d never seen them before. “You like ‘em? Why not come have a feel, then?” He’d laugh and give a cheeky wink.