Matsuru Kami

From Aerandria Scans:

Kiichi and Kanoko are brother and sister who have just lost their parents. They move to the deep countryside, to the home of their relatives the Toba family. And who is Toba-sama? A hearth-deity who has been watching over the Toba house for 150 years. He uses abusive language and is very ill-disposed, but he’s a softie at heart and has a strong protective side. And this deity names Kiichi for his successor! The life of the two siblings is about to change at 180 degrees! A countryside-life fantasy that will fill your hearts with emotion!