Story
Some need to know information:
Popotan the anime is completely different than Popotan the game.
Popotan is riddled with generic no-name and/or relation association designation characters, so special dispensation is required for the latter category, for they make up most of the supporting cast, and are significant to the plot...
Section: 0 contains all of the primary characters.
Section: 1 contains characters exclusive to the VN.
All of the subsequent sections are the the generations of offspring by the primary characters as they appear chronologically. (IE: section 2: 2nd gen, 3: 3rd gen, and 4: 4th gen.)

(Anime)
The three sisters Ai, Mai, Mii, and their housekeeper android Mea inhabit in a mysterious house that transports them through time and space. Following leads obtained from dandelions aka "popotan". The sisters journey, convinced that the naked silver-haired woman in their dreams holds all the answers to their questions.

(VN/H-Game)
The player assumes the role of Chris, the protagonist of Popotan. Chris is a high school dropout and refuses to get a job. He wanders playing his guitar for spare change. After an unsuccessful attempt to swipe some food from a cart near shrine entrance, he finds a convenience store, where he gets directions leading him to the mansion. He enters without asking permission and runs into the three sisters and their lifelike android maid. Chris asks permission to stay because the rent is cheap and the girls are pretty; they consent, but force him to take a part-time job. The convenience store owner hires him, and as the story progresses...
(Source--most from Wikipedia)