Pedro and Charlotte are sparring in a friendly match at the Langham hotel, which UFC organised after staff at the organisation saw a Herald story about Charlotte where she revealed she wanted to become a UFC fighter.
Last month Charlotte, who contracted deadly meningococcal disease as a baby and had to have parts of all four of her limbs amputated to save her life, told the Herald on Sunday she'd recently taken up boxing.
"It lets out my anger, I have so much build-up in my physical self sometimes that I just have to let it out," she said.
Now, after sparring against Pedro, she's one step closer to achieving her dream of fighting professionally.
Charlotte said she was scared ahead of the training session - Pedro is her favourite UFC fighter.
But her nerves wore off pretty quickly.
"I didn't know what I was getting into. It seemed like 'Oh God, I'm going to die' and then I got used to it and the adrenaline started kicking in.
"It was scary, definitely. But you need to learn how to control that fear - it never goes away, ever."
Pedro said sparring with Charlotte was an "experience" for him too.
"I got dropped a couple times. She hit me pretty hard in sparring which I wasn't told before I started.
"She's a pretty amazing girl and I think it's more inspiring for me to be here than her."
Charlotte's a guest of honour at the UFC event this weekend.
On Friday she attended the fighters' weigh-ins for Fight Night.
And today, she'll watch the much-anticipated match from her front row seat at the arena with her mum Pam and trainer Heidi Collins.
"Apparently [the seats] they're like $13,000 which is an insane amount of money," she said.