Wilbur- Top of your head, because of your height differences it's where he can reach the best, and it feels very sentimental to him, plus it makes him feel tall and dominant over you.
Tubbo- Your cheek. He likes taking your face into his hands to squish your cheeks and kiss them.
Tommy- Lips. He loves how it feels to be so close to you and how soft your lips are on his.
Fundy- Floris likes your jaw especially in the back just before your ear. It feels nice to him, being so close to your neck, which is such a vulnerable spot.
George- Your cheek. It's so simple yet he adores how your face flushes when he does it.
Dream- Your neck. He loves how your breathing studders when he does it and how you get all flustered.
Sapnap- Shoulder. He does it a lot when he's hugging you, he'll lean down and pepper your shoulder with kisses.
Eret- Forehead. It makes him feel a sense of dominance over you, which he likes.
Quackity- Lips. He loves kissing you and feeling you kiss back, reminding him that you're giving as well.
Karl Jacobs- Anywhere. He loves being able to give you as much love as possible through any way he can.
Awesamdude- Your wrists. A lot of the time you'll rest your hands on his face and his mouth will align with your wrists and he loves kissing them gently.
BBH- Cheek. It makes him feel like you trust him, which you do, but he loves how it feels like it's more true.
Schlatt- He likes kissing below your ear because he can smell your shampoo and feel your warmth.
Jack Manifold- Temple. It's a place he can absentmindedly kiss and still make you feel loved.
Technoblade- He likes kissing your forehead. It gives him a sense of comfort.
Ranboo- Anywhere. He would most likely kiss you anywhere he got the chance to and has definitely attacked you before holding you down and kissing you all over.