Thread:PencilDJ12/@comment-24342918-20140117134640/@comment-25301601-20140118052612

They may be nuzzling in the art, but it is still unknown.

There's more than just this. Like for example: This is a picture of Toad and Toadette holding hand in the Congratulations Screen of Mario Kart Wii. They were described as friends, siblings, and partners, but Nintendo didn't say if they were in a relationship. Therefore their relationship is still a mystery. Same way goes to Yoshi and Birdo.