Your oc or the oc's crush ends up stealing an infinity stone. Or one of them come in contact with it. Out of every stone.. what stone would be chosen? How would it get in contact with you/crush? Will it be kept? What would be done with it? Would it be used for good or bad? Would Thanos be beaten at his own game by his own plan? Were you driven to it? Did Thanos ask you to do this? Would you do something else? Put yourself into the role and chose your whole entire story with the infinity stone. Did you steal them all to keep them safe from Thanos or to be the villain yourself? There are so many ways this could go and whatever happens is your choice.