And apparently she's a little freaked out by all the grown men dressing as Eleven.

"Stranger Things" star was just on "The Tonight Show" to promote Season 2, and she was a delight. Millie talked to Jimmy Fallon about the new season, and since she rapped the last time she was there, he had her get up and do it again.

So here's Millie rapping a recap of what happened last year on "Stranger Things" Season 1:Rap goddess/queen angel. Perfect.

Millie talked to Jimmy a tiny bit about "Stranger Things" Season 2, even though he hadn't watched it yet. She shared the mini "spoiler" that Mike and Eleven kiss again, and shared behind-the-scenes details about the kiss: You probably noticed a lot of fans dressed as Eleven for Halloween. Millie told Jimmy it's cool, but if she thinks about all the grown men dressed as her it freaks her out a bit.

But for her own Halloween costume, she went as Baymax from "Big Hero 6." In this video, she shows off her costume and dances a bit. She also said her father dared her to go to a hotel front desk and ask for a room key dressed as Baymax. Also, she's a big Kardashians fan? Eh. To each her own... "Stranger Things" Seasons 1 and 2 are now streaming on Netflix. Plans for Season 3 are already coming together.

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