To be fair, until you get a magical robe, there's no reason for Gale not to be naked all the time anyway <.< >.>
I did a full pyjama party run at one point, where everyone had mage armour and mage armour was the best, or near best, option for them, so everyone fought in their undies just because. Good times.
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the other thing to mention with trying to tease out the Gale romance is that as well as resting every time his approval changes, also make sure that you rest every time you complete any kind of cut-scene action that involves a decision; even if his approval doesn't change, he often has a flag acknowledging how you handled it, and these add up in the background as well. Basically, keep him in your party and sleep any time anything happens at all.
