You know, all he was doing was simply going for a relaxing stroll, to work the kinks out of his neck and shoulders from all the breath poison that he's been doing. That would take him vaguely in the vicinity of the kelpies, yes, but Ignis has a beautiful thing called 'common sense' and won't fall for cheap ploys. Also, he stays away from the water's edge a decent bit.

....Which is more than he can say for the lass apparently antagonizing the surface of the water.

He doesn't say anything right away. This isn't his circus, nor his monkey. But he does, just to see what happens next, linger around and lean against a tree.

He wants to see if she either almost get drowned, or smack a horse. Either would be interesting.