You're in his kitchen, having a drink (apple juice of course, no alcohol in front of humans) and listening to him explain in a monotone voice about his Noble-prize winning science experiment (what the experiment was you have no idea). You are watching his eyes dance, giving away his excitement and need for approval. You note that his experiments these days are about disease and the environment, instead of weapons and technology and you realize what a man he has become. You nod your head in approval, examining him the whole time. He reaches for a knife to cut the apple in front of him ('all by himself!' you think, proudly, laughing at the absurdity of how you treat him like a baby) and see him cut himself on the sharp edge.
You reach out and touch his hand. "I'll heal the cut" you say, but his big hand engulfs your small one. He lets go quickly, and you place the tiny hand on the cut and let the sparks flow through, connected yourself to him. The warmth floods through your body, and you sigh involuntarily, and blush fiercely. You see him trying to resist the laughter that bubbles up, but he lets out a little squeak, now it's his turn to blush.
You finish healing the cut, small as it was you managed to make it last, then you grab his hand. He looks up into your eyes and opens his mouth, and shuts it quickly. "We've had this talk too many times." he says, regret evident in his face.
"Way too many times, and we agree, too old, too weird, different worlds, different species. Not a convenient relationship." You say. It breaks your heart every time, and yet you still manage to get into the same situation, again and again. In the romantic novels you read at night, all the relationships are too convenient. Even in a seemingly inconvenient and impossible situation things change, and everybody ends up happy. That isn't how the real world works. You are still waiting for that convenience. You hoped the magic he had gained from the time tunnel (which he still pretended not to have, and you secretly believed he never told you because he liked when you touch him, heal him) would change him into a faerie, or immortal, but it didn't work the same way as a faerie's. He seemed to have more control over it, and he didn't need to replenish his stores nearly so often. Why would it work out the way you wanted it to? Nothing else in your life works that way. So you are forced to watch from afar, wishing that you could be with him.
You both realize at the same time that it is time for you to leave. He politely walks you to the door, like a good gentleman should, and you wish he wouldn't, his presence is intoxicating. You open the door, and shield. Before you leave you catch a glance of his forlorn face, and succumb to a moment of weakness. You fly up to him and press your lips lightly against his. He instinctively closes his eyes, and tries to draw you closer, forgetting that you are invisible, and are not the same height as a regular woman. You laugh and kiss him on the cheek, knowing that it'll be weeks before you can safely visit him again. A hard sacrifice, and as you fly with the wind in your hair, and smell the fresh air, you realize you'd give it all up for one simple convenience.