On a sizzling summer day in Yukinari's backyard, Kirie, Miharu and Koyomi get wet 'n' wild in a kiddie pool. But when a jealous Fukuyama gets wind of the girls in their pool party threesome, he turns the poolside pleasure into a house of hot horror. Later, the door slams shut on a trip into Fukuyama's mansion, where a big erotic trap is set for the girls! But no need to fret about these lascivious ladies--it's nothing that a sexy soak in the bathtub can't fix.

Yukinari Sasaki
A short high school boy who has been mistreated by girls so badly that he's developed girl-phobia.

Miharu
This story's heroine. A kind and sweet alien with an enourmous appetite.

Kazuhara Fukuyama
The self-proclaimed "most handsome guy in Mizuno High School." He is hot, rich, athletic, and totally perverted.

Risa Fukuyama
Kazuhara Fukuyama's occult-obsessed younger sister.

Koyomi
A Sirenese agent who is afraid of men and has a hard time living on Earth. She’s been charged with finding a husband for Miharu’s sister.

Kirie
She lives next door to Yukinari, and is his childhood friend.

Tomoka
An adorable agent from Siren who may look like a child, but hates to be treated like one.

Ebi
Miharu’s cuddly pet. The name 'Ebi' comes from the fact that she looks like a shrimp.

Mario Kaneda (?????)
Other works by Kaneda-sensei include Farland Symphony, MMR (Magical Maid Ruri), and Romance wa Ken no Kagayaki.