OTF

OTF is short for One True Friendship. It's basically the platonic version of OTP. If you want to talk about your favorite characters friendships, without having people think you ship them, just use OTF.

Person A: Oh, I love insert character here and insert other character here's relationship!
Person B: Oh, do you ship them?
Person A: No, I don't, it's more like my OTF.
Person B: What the heck does OTF mean?
Person A: OTF is short for One True Friendship.