It DOES look like more than one type of grass in there :-) The Malepartus should produce the long, delicate, thread-like seed heads - the fat puffy ones look like they belong to some sort of Pennisteum or fountain grass.

No doubt about it, there are two different grasses in one planting hole--- looks like you got two for the price of one. You are going to have to dig it up and separate them or try to pull the Pennisetum out when the soil is moist, like after a good rain except it already looks a bit large for that. I'd dig it up, put the roots in a bucket of water to get rid of the soil, pull them apart to separate them and then replant. Since they are blooming, it'd be best to wait until late winter or early spring.