Come to think of it, between the knowledge of germs and the need (well, "excuse") for disinfection, this world does seem to have a higher understanding of medicine compared to your usual fantasy setting.
Or maybe it's just Centipede girl (and her ilk) who has that knowledge. Being able to mimic other animals to a near perfect degree does seem to imply having some kind of intuitive understanding of biology.
(Ignoring the fact, of course, that licking one's wounds to 'disinfect' it is actually BAD idea because of the sheer number and variety of germs found in the mouth. Granted, there are some other components in saliva that have bactericidal and wound-healing properties, and animals do benefit from this practice, but for humans it's all in all highly inadvisable unless you wind up stuck somewhere without any access to antiseptics, or soap, or even just plain clean water... which is to say your options are then the same as any other animal's.
And of course letting someone else lick your wounds is even worse because they'll probably carry some germs that your body don't already have. So it's another vector of transmission. Letting pet cats and dogs is even worse [cats especially].
Though, maybe centipede gurl's saliva works differently and hers is a potent antiseptic. More likely she's just pulling his leg though. And in any case, with that guy's body and constitution, he probably can just give germs the Chuck Norris treatment and shrug them all away. Literally.)
And of course letting someone else lick your wounds is even worse because they'll probably carry some germs that your body don't already have. So it's another vector of transmission. Letting pet cats and dogs is even worse [cats especially].
I have a feeling she wouldn't care even if she knew all that. After all, she views him as food.