Your apartment. Not 'our'. Combined with Viktor wishing he were strong enough to end their bond, the initial shock of it feels like ice water being thrown in his face. It's hard to quell the feeling of rejection it causes even with Viktor in his arms like this. He came back to Folkmore, but maybe he hasn't come back to K.

"Of course it's all right. You live there too." Finally releasing Viktor, K turns away for a moment under the pretense of taking in their surroundings to orient himself, and uses that opportunity to discreetly swipe at his stinging eyes and compose himself. "If you still want to," he adds before reaching for Viktor's hand again, so they can start making their way out of the swamp.