[His own attention had shifted to the gravestones, spotted with moss and now damp with vinegar. Alucard, of course, was still of interest, but the state of the stones themselves....]

Forgive me, I was curious.

[A poor explanation, but the only one he'd be giving, and to be fair it was honest enough.] ... Vinegar will cause the stone to crumble. Simple soap and distilled water will preserve their names far better.

[Because indeed, that was a matter that for the moment, took some obvious importance here.]