Integral sat at the table, and motioned for Kon to do the same. "Still, I know what you do is important, and I normally wouldn't call you away from it."
She sighed, then sat up straight, steeling herself. "You're aware that the vampire Alucard is here. You're also aware that I share a rather long history with him. He has become human, due to the superpower thing that happened."
Just facts. Start with the hard evidence. "You are a wonderful companion, and an incredible lover. I wish that our lives were less insane, because I would have enjoyed sharing a deeper relationship with you. However, our lives are what they are. We cannot really change that. Alucard's being human takes away the reason we held back from each other. I don't know his feelings on the matter. I try to avoid talking to him about it, honestly. But I cannot in good conscience continue a physical relationship if I may choose, somewhere down the line, to be with another person."