https://www.youtube.com/watch?v=F9AmWVxvfb8
At 11:08
This game is like the original Mario Bros (the one with the turtles, crabs and annoying fire balls) but with many different enemies (like penguins and even Pikachu), different structures, many characters (from Vocaloid) with many attacks and boss fights
The boss of the third stage is Meiko, she will appear on screen and will turn big, all of her attacks are heartshapped kisses and she will change the directions when you hit her enough
She is also a playable characters but she only attacks with a castlevania-like whip