Somehow, my immediate family--that is, my parents, siblings, and I--had come into possession (perhaps accidentally) of a text outlining some kind of Lovecraftian ritual. We didn't really know what it was supposed to do (I think it was more of a vague evocation of eldritch powers than a specific summoning) or whether or not it would work, but we were going to try it out anyway. As a family. A night of appropriate occult significance was coming up soon, and also we had access to a cabin on a lake which we thought was similarly significant. I had a little more belief that it would work than my family, and a lot less certainty that it would be a good idea, but I was interested and I agreed that the perfect opportunity to try it was going to come and pass soon. And, anyway, I knew they were going to try it, so I felt I'd better be there and try to mitigate whatever damage resulted from it.
We arrived at the lake in late evening. We were far from any city lights, and the treeline all around us was a wall of solid black, while the sky was a dark and starless blue. The lake itself was black and calm, but there were subtle lights in there from some bioluminescent life, and a rock dropped into the water triggered more of that phenomenon in a tiny, blue-white explosion at the center of the ripples. The whole lake seemed to strain with potential, like a boulder perched on a cliff.
We got to work at once, all of us arrayed across the shore, staggered rather far apart and facing the water, reciting our parts from unbound pages. I don't remember any of what we said. Occasionally, lights and indistinct emanations appeared from the lake at the end of the dock, the point which was the focus of our ceremony. Some of these merely dissipated, while others would stream away from the lake and into one of my family. This had no obvious effect, but still I did my best to prevent it from happening: I held out my hand in a certain gesture, as if in benediction, which--along with proper concentration--pulled the eldritch emanations into that hand, where they apparently dispersed. I felt no adverse effects from doing this, and had no idea just what sort of trouble I was protecting my family from, but by this point I was of the opinion that if we could just get through the ritual with no lasting results whatsoever, I would call it a success. We were getting to see something amazing, and that should be enough.
Eventually, the ceremony did come to an end without serious incident. It was then that we found a package addressed to us: a box wrapped in white paper, with a note. It used language that suggested the whole package was put together and sent right after we completed our ritual--even though that had only been moments ago--and said something to the effect that, since our efforts had gained us nothing of value, the sender wanted to provide us with gifts that might placate "those of an acquisitive nature". Within the box were five smaller bundles, each wrapped in more white paper and marked for one of us.
In a detached, audience-perspective way, I knew where the package had come from. It hadn't been sent moments ago, but instead was left there before we'd even arrived by the mysterious man who had given us access to the lakeshore cabin. He had known we'd perform our ceremony before finding the box, and also that we'd gain nothing in the attempt. His gifts were chosen to satisfy our individual Faustian desires, and thereby prevent us from ever trying this again, and continuing down what he knew was a dangerous road.
Also, I knew that our hidden benefactor was an age-old vampire who had watched over and protected our family.
But the whole package was destroyed before we could take the gifts within. I don't remember how, only that it seemed inevitable.