John barely breathes as Martin's lips gently press against his chest. Martin has kissed his scars before, but not that one, and not with such... potency. On paper, he might have worried about the physicality of it, the relative sensitivity of his chest and the odds of it provoking an unwanted reaction, but now, such worries seem absurd. If it's too much, it's not because of how soft Martin's lips are, or the warmth of his breath ghosting over John's skin. It's because it's so goddamn tender, the gesture imbued with so much love and care and bloody reverence that John has to look away, gaze fixed on the wall and lips pressed together tightly so they won't wobble. There is no risk of him enjoying this too much. It's all he can do to endure it.

It isn't until Martin shifts into a more familiar, less fraught lean against him that John resumes breathing properly, as if he's finally been given permission. He swallows again, his arms lifting to curl around Martin's back. The thanks that follows is enough to put paid to his tenuous composure, and John lets out a rather damp huff as he pulls Martin closer.

"Always," he murmurs into Martin's hair. "Every time." He knows it's not a promise he can keep; he also knows he might keep it better here than anywhere else. "I love you so much," he adds in a damp, self-conscious rush. It's too genuinely meant to be ridiculous, but Christ, it feels close to that line. He needs a shirt and a bloody drink, but for now, he stays put, pressing a kiss to the top of Martin's head.