Caidance is only a couple inches taller than Echo and she’s probably be intimidated by Gideon. She’s always been slightly frightened by taller people, especially men with the exception of her lover.
Unlike Killy, Gideon is absolutely fine being a teddy bear. While his size may be intimidating, hardly anything else about him is and he tries hard to act in a way that counteracts what his size might suggest. (He also feeds the stray cats around the Tower and and will shelter them in his room on really cold nights.)
Also there, now he has a teddy to sleep with since every one thinks he should have one, lol!