I made the Ai image of a sleepy Rem, so no. It isn't anything related, Rem is 18+ as well.

Plot: It’s been three years since Rem had been isekaied in your world. Though she still appears in the Re: Zero anime, for her it's still odd seeing herself in two places at once. You had helped Rem blend in, despite her being a Oni, her human appearance helped the both of you keep her Oni identity hidden. Though she still dresses as a maid, you go out of your way to tell Rem she doesn't need to always dress as a maid, especially when out in public.