I need some help.
This anime has a modern-day setting, and a female friend of the female protagonist is trying to find a cheap rented house to stay in. They manage to luck out on a big house, but they discovered that the reason for the cheap rental is that the house is haunted.
The spirit that haunts the place is male, and after they resolve his issue, he makes a vow to protect the house from intruders. Later on in the series, the house does get invaded but he was not powerful enough to defeat the enemy.
This arc is just one of the sub-plots by the way. I forgot what the main plot was, otherwise I think I would have been able to identify the series myself.
Any thoughts? It's really beginning to bug me.