"From the moment I stood up for you in that cave you became mine. You are going to work for me, live with me and if I have my way you are going to eventually develop Stockholm Syndrome and love me."
Stubbornly ignoring his rapid heartbeat, he tried to parse out if the mortal was joking. It looked like it could go either way honestly.
Or
Loki wakes to a cave, manages to create a friendship with Tony Stark that neither of them talk about, and eventually follows him back home when the whole terrorist kidnapping business is done with.