Recommendation of ऐनीमे crossover couple?

Since three years ago, I have a really huge addiction towards crossover couple. (I ship them और than तोप couples) Crossover couple is where two different animes combined together. Examples are:

Lucy (fairy Tail) and Luffy (One Piece)
Ikuto (Shugo Chara) and Taiga (Toradora!)
So, what's your प्रिय ऐनीमे crossover?

Mine is चालट, चार्लोट, शेर्लोट Dunois (Infinite Stratos) and Kise Ryouta (Kuroko No Basket)