Tenshi ni Naru mon! is the story of Yuusuke Kamoshita who is living alone until he literally stumbles across a naked girl in a forest, a very energetic girl named Noelle who claims she is trying to become an angel. Noelle and her entire family proceed to move into Yuusuke's very large home and disrupt his life. Silky and her minions interfere as the series goes on.

(Source: Wikipedia)