VGFacts

I've been playing Crush Crush for a while and I found a Mario reference. If you flirt with Mio there is a chance she will say "Your princess is in another castle... JK!" which is a refence to Super Mario Bros. when toad says "Thank you Mario! but our princess is in another castle!"
EDIT: I've changed the name of my thread because I've found more references in the game.

Reference in question.

I've also found another reference by flirting with Mio (Why did I choose to play this game?)
If you flirt with Mio there is a chance she might say "Player used Seduction. it's super effective. Mio fainted..." this is a reference to the Pokemon games when using a move, using a move that is super effective against a specific type Pokemon (like if you use a fire type attack againt a grass type pokemon) and when a Pokemon faints in battle after losing all of its HP.

If you atone Mio, there's a chance she'll say "Quick - top five games! (Please don't say Fappy Bird... )" Fappy Bird is most likely a reference to the game Flappy Bird.