Being Teddy Bear means that you are homosexual/ loving femboys/ hating women for no reason.
Teddy Bear is a widely known figure who's notorious for hating on women/ being homosexual, so if your friend says "He's trying to be Teddy so bad" Now you know.
"Did you see how Anne Frank might have been gay?" "Yeah, she's Being Teddy Bear so bad."
"Dude did you hear how Derek hates women because he likes femboys?" "Dude, he's literally Being Teddy Bear." "Who the Fuck is Teddy Bear?" "Make love with me."