For centuries they've watched Earth. For centuries they've watched then slow destruction of the planet. The watchers have hoped the humans would repair their ways. That they would learn to respect the Earth and protect her. The time has come however, if the Earth is to be saved then the time to act is known.
They send a vast ship and it blocks out the sun. Smaller ship land on Earth, collecting the flora and fauna for preservation. One alien lands near a farm and finds himself confronted by a woman determined to protect her animals. Her land is well cared for and thriving, unlike the abused Earth in the farms surrounding.
The alien decides she deserves mercy. She's a gentle soul, kind to others and she respects the natural order of things. So, he takes her. Against her will, he takes her to the vast ship and saves her.
She watches as her race is wiped out, she watches as humans, as all living creatures are destroyed.
The ship lives as others arrive to repair and replenish the Earth. When it's time, life will be restored.
This role play can be as dark or as light as you imagine. The alien could be happy he found a human worth saving, he could be gentle and loving with her. Or, he could see her as worthy but still lacking. He could desire to punish her for her kinds deeds. He could hurt her.