Gratitude slips out in a soft murmur as Martin reaches for the bottle, but he stops when the real meaning of John's question settles in, blinking at him for a moment.

"Oh," he says, too tired to be properly embarrassed at the idea. "Y-you mean—?"

Well, there aren't many ways to interpret it. John's offering to help him; to wash his hair. And actually, it sounds lovely. Not so different from what they already do, constantly carding their fingers through one another's hair. And John's offered.

"Yes, I..." He smiles, sheepish, ducking his head down. "Yeah, that'd be nice."