It's meant to be vague. It's most likely talking about Ichima, yes, but it could also be a challenge to Ichima. Additionally, the Ichima we know looks different from the Ichima the old man was talking about and is definitely gloomier. It could be that "Ichima" is an end state of the negakari and they have a time when they run around as kyuuki in the real world before going to stay permanently in the nedoko.