Kenta can't concentrate on his exam studies because of his parents who are always fighting. During summer vacation, he ends up being taken care of at his aunt Saki's house. Living under the same roof with Saki, whom he has admired since childhood. He can't concentrate on his studies at all because he's worried about her soft-looking big breasts, even through her clothes. To solve Kenta's troubles, Saki proposes an obscene refreshment method...
