I'd have to say it's a tie between D.N.Angel, Gundam Wing, and Naruto.
In D.N.Angel it's very obvious that Satoshi has a thing for Daisuke, and I'm pretty sure the feeling is mutual.
Gundam Wing... If I were to say every reason this is slashy it would take me hours...
In Naruto Sasuke and Naruto accualy kiss and later on in the episodes there is a large abundance of fluff between the two.
In D.N.Angel it's very obvious that Satoshi has a thing for Daisuke, and I'm pretty sure the feeling is mutual.
Gundam Wing... If I were to say every reason this is slashy it would take me hours...
In Naruto Sasuke and Naruto accualy kiss and later on in the episodes there is a large abundance of fluff between the two.