Let's go to a hot springs and fill 24 minutes with basically naked teenage and elementary girls who talk about their "father" while cleaning one another.
Let's spend some screen time with the father-figure liking the near nakedness of those in his care.
Let's add in "friends" who are supposed to be supportive of the unexpected and tragic circumstances that led to a college student getting custody of his nieces but who really just encourage incestuous thoughts and activity.
Let's throw in some jealous characters who are willing to strip themselves to get the guys attention.
What's the result?.
It is a predictable ending, but still adorable. Very good turn to give the final touch to the story and close the main threads created. A very nice ending, to let everyone sleep peacefully.