Mine is an Arilou from Star Control 2, one of my favorite games of all time. They are the aliens that have been seen around earth, showing up in flying saucers and abducting people. They watch out for us, occasionally changing little things about our species to protect us from extra-dimensional parasites. They seem to have some long term vested interest in the well-being of humanity, but nobody knows why...
Arilou: "Our motives are multiple, our desires complex. Part of what we do on Earth is for your own protection. There are parasites. Creatures who dwell Beyond. They have names, but you do not know them. They would like to find you, but they are blind to your presence, unless you show yourselves. The Androsynth showed themselves, and something noticed them. There are no more Androsynth now. Only Orz...In a way, ignorance is your armor, your best protection. They cannot see you now. They cannot smell you. Much of our work with your people involved making you invisible, changing your smell. If I tell you more, you will look where you could never look before, and while you are looking you can and will be seen."
"You do not want to be seen."