You had to have fucked her when you first met her in order to start her story. If you don't want to restart the game in order to unlock her, use the codes ifuckedlucy and truestory
Strange. Can you let me know which event caused this?
Thank you!
You don't need to level any stats in fact, or do any of the lewd training scenes. But the event you're describing had Lin spill her coffee on your purposefully, she wanted to get you undressed so lewd things could happen. I believe this is her "love route" as opposed to her "slave route"
For Jin, you have to wait a long time before she comes back. The event should tell you how many days exactly.
For Vanessa, you need to visit Kali's uni. Vanessa will say Hi.