You had gotten all dressed up in an athletic outfit and went to participate in the Tournament with Fiona.
(Y/N): Where is she?
And like clockwork, she came ... wearing something ... interesting.
Fiona: Hello (Y/N).
(Y/N): Wow. I ... wow.
Fiona: Is there something wrong?
(Y/N): No ... you just look really really cute!
Fiona: Thank you. OH MY GOD!!! EEEEEE!!!
(Y/N): Why exactly are you in that gettup?
Fiona: It's something personal.
(Y/N): Is she a spy? I mean the disguise and an event like this?
Fiona: Are you ready?
(Y/N): YOU BET! HIT THE SONG!!
On it.
You and Fiona consistently went through each match, with both of you winning them.
Hell, the two of you have a great teamwork dynamic!
By the final match...
The Tennis ball was being launched past the both of you!
(Y/N): OH NO!!! HERE GOES!! KAIOKEN!!!
Fiona: Wait, Kaio-wha-
You slammed the tennis ball right into the opponent's racket, which caused it to shatter, and thus leaving you and Fiona the victors!
Later...
Fiona: You're giving it to me?
(Y/N): Hey, you wanted to do this, so we do it together.
She blushed and hugged you.
Fiona: Mind if I come to your house later?
(Y/N): Of course not. My harem is going to love you.
And with that, the glass shattered in her mind.
Fiona: H-Harem? WHAT THE FUCK?!
(Y/N): You okay?
Fiona: Oh yeah, sure. AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGH!!!
She was internally screaming even when getting ready.