Those mosquitoes have paid you out for that pastille—by Jove, they have!
Perhaps he exhales a delicate scent, as he chews a pastille.
A pastille (lozenge) is a disc-shaped sweetmeat, but a pastel (crayon) is a pencil made of coloured chalk.
There was, even on the little stone staircase, a faint odour of pastille or scent spray, or something of feminine suggestion.
But upon ...