The kiss is far more of a relief than a surprise. It's barely a surprise at all, in fact. It's what Martin would do — just like forgiving him an inhuman transgression, or stubbornly drawing him out of a gloomy spiral, or holding him close while he recovered his equilibrium, or gently coaxing him into the kitchen to make a bolstering cup of tea that would fix everything. This is always who Martin was; he didn't need to grow into his potential as much as John needed to become the sort of person willing to see what was on offer and embrace it.

But he has, and he does, leaning into the cradle of Martin's hands and returning the kiss with a soft hum. He lifts a palm to Martin's cheek, lingering at his lips for a few dragging seconds before drawing back again, seeking his gaze.

"You don't owe me anything," he murmurs, gentle but firm. "And I don't want to do anything that either of us might regret. But if... if you want this," he says, brushing his thumb along Martin's cheekbone, "then Christ, I want you to have it." He swallows a bit thickly, letting their foreheads rest together and his eyes fall shut. "I just need you to be okay."