Kousuke is a high school student. He has just discovered that Shizuka, his childhood friend (whom he has a crush on), is now attending his high school. However, they have not seen each other since they were five years old, and much has changed. At first, they do not like each other, but they accept each other's differences and continue their friendship. They carry on with their lives until small events begin to escalate, and they start to show affection for one another. Meanwhile, Kousuke's good nature, lechery, and luck lead him into the beds of various other young women as he attempts to solve their problems.