Quote from coffee_11
Eroge are games. Maybe he's looking for game-adapted manga?
Maybe. At the same time, what's a "borderline eroge"? It's either eroge or not; sexual content or not. There ain't no borderline.
If that's the case, however, here's some categories:
Based on a Visual Novel
Based on an Eroge
Though I'm pretty sure he meant "borderline H".