I can do anything I set my mind to.
Buddy: Usagi because WHO ELSE IS THIS DELIGHTFULLY NAIVE AND SWEET. And instead of realizing she is human and rediscovering her family, she has to reawaken her fellow Senshi as soldiers of justice. Even though they are grumpy and reluctant civilians, she eventually succeeds because she is adorable.
The dad: REI HINO. All Usagi wants to do is build gingerbread houses with her but she is too busy being grumpy about it.
The mom: Mako. She would eat the maple syrup spaghetti dish Usagi made for her. She WOULD.
Michael: Chibiusa. Usagi somehow needs to introduce herself to her own daughter (because she only knows NeoQueen Serenity). Hilarity ensues.
Jovie: Mamoru (generic love interest is generic)
Papa Elf: Luna, who conspicuously keeps plot-relevant information to herself until the moment Usagi needs it. Damn it, Luna.
Santa: Setsuna, breaking some taboo or another to keep Usagi and her friends separate until the timeline can be repaired or something. She does that. And then at the end Usagi needs to get all her new friends to believe in their power in order to save something that Setsuna is doing to invariably mess with space or time.
Miles Finch: Ami, the only one who Rei respects and is hailed as Brilliant.
Dad’s bumbling coworkers: Minako and Haruka. (As children’s book authors.)
Deb the secretary: Michiru (I just want her to be in there somewhere)
Polar Bear, Arctic Puffin, and Mr. Narwhal: Naru, Umino, Ms. Haruna; members of the world she leaves behind once she discovers her true identity. She never goes back.
BONUS: Usagi’s Christmasgram to Rei. “I’m… I’m here, with my planetary guardian, and we’ve never met, and she wants me to sing her a song… And, um, I was reincarnated, but you don’t remember the past… So I’m here now, I found you, Sailor Mars! And guess what? I love you! I love you! I love you!”