This takes place after the big battle against the shredder.

The turtles drive into the parking garage where you and your family are standing.

Mikey: Hey, y/n. I have a song to sing to you. You're gonna like it.

Mikey turns on the music and sings (pick your favorite love song). This annoyed Leo, raph and Donnie they cringed at how bad Mikey tried to sing. Your family didn't seem to mind at all.

Raph: get back in here, Mikey! *pulls Mikey back into the turtle van*
Mikey: come on, guys. You nearly ruined the moment.
Leo, raph, and donnie: shut up, Mikey!

Mikey then opens the van ceiling door and continues to sing out loud to you. Even you had to blush at Mikey for you had a crush on him since you first met him.