I just had an idea
Imagine this one time, Loki and Grandmaster are alone, and Grandmaster is talking about how he wants a blue suit for Loki, how it’s his favourite colour and how it would look so good on him.
And Loki is like “Bet I can make you want me even more”
And Grandmaster is like doesn’t understand and then Loki just turns BLUE, cause we all know he can do this, being a frost giant and stuff
And Grandmaster just can’t handle it anymore thinking “I want him so much”
And Loki just has this smug smile of his on his face being extremely pleased with himself but actually incredibly touched that someone actually not only accepts him as he is but prefers him that way.
And it becomes their little thing where Loki can be blue all he wants when they are alone and Grandmaster is just so fascinated by this man and wants to get him no matter what.