Iro Yoridori / イロヨリドリ

Main character, Shigeto Hirata had a negative character, and were weak in good terms, and the existence to be able to tell to be a friend spent days only in Mizuki of the Childhood Friend to be inconspicuous as much as possible.
One day Shigeto witnesses the Hasegawa which is a famous spear Japanese spaniel man and the Sex of the girl of the classmate at school by an unexpected coincidence.
Shigeto who learns Immorality-like Koufun in the Sex which I saw in front for the first time of the same age, and often looks in the Sex of the Hasegawa from Koukishin after it, and comes to see it.
But the Devil's temptation of the Hasegawa comes to gradually extend to the girls of the acquaintance of Shigeto, and grow to Mizuki of the Childhood Friend at last...