No, the younger girl, in the original game, is I believe a co-worker from MC's job, she is also his kouhai. Then aside from training/abducting Hazuki, you do have the option to drug the young girl, and either sleep rape her in the bathroom of the work building, or also I think you do have an event where you can outdoors fuck her in the park (after training her in a similar manner as Hazuki), one (if not her only ending) is leaving her there after you are bored of her, and she is fucked by the homeless people wandering there. Her and Hazuki are two completely different characters altogether. I think the CG just kind of strings the kouhai's sex scenes along the way, which can confuse some people who didn't play the original game, hope this clears things a bit, and if I'm mistaken in something please correct me if I'm wrong.
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