Doubt!
1 parts
Ichiru Kanzaki is given an offer he can't refuse: to clear his entire debt, he has to enroll in the high school where his father works to track down his father's illegitimate daughter, his own younger half-sister, whom he has never met. But which girl is she? (Source: MU)
Parts, ranked
Every entry of this series by aggregate score — the sub-ranking inside the ranking.