Stray
Hana recognizes the shy, quiet, skittery, jumpiness.
She's seen enough of it before.
Shinobi never treat ninja hounds that way, but enough villagers neglect enough dogs that eventually make their way into her clinic so that she's seen it all.
Strays are always the same.
They are so grateful for the least little look, morsel, or pat you give them, yet so very afraid to accept it because they might have to lose love and affection again.
Yes, she's seen enough villagers do it to enough dogs.
But Hinata is the first kunoichi she's seen that's been treated that way.