I would have a slight plant ID advantage since the same flowers are plentiful at my daughters house. Cats are highly allergic to most varieties of lillies and reactions have been known to be fatal. Paul
They're lilies in a flower bed (shared with hostas, peonies, and others). I don't know what kind. They're almost as much of a cover as a bloomer. Our irises are in another bed and look a bit similar as they're sprouting.
I didn't know lilies were harmful to cats. They certainly don't dissuade deer from dining and ground hogs/woodchucks from digging.
I don't believe it's grass, rather I think it's a flower bed, possibly lillies. So if I'm right about them being lillies then I'd title this Kat Killer. Paul