Ok, here are some more. Some are dirty!

I want to get my basilisk into your chamber of secrets.

You know, Hagrid's not the only giant on campus.

You know, the Sorting Hat placed me in Gryffindor. I think it's because like Godric Gryffindor himself, I too have an impressive sword.

Want to have a Tri-Wizards Tournament? Well not really "Tri-Wizard," I was thinking more one wizard and two witches.

I've been whomping my willow thinking about you.

Do you know the Petrificus Totalus spell? Because you make me stiff.

I'm not an Animagus but sometimes I can be real animal.

You know Platform 9 and 3/4? Well I know something else with the same exact measurements.

A couple nights with me and Moaning Myrtle will have to get a new nickname.

Wanna practice making what looks like a mandrake?

You look like you'd be a good Quidditch player. Want to ride my broomstick?

The thought of you makes something vast and silver erupt from my wand.

They say I'm like the horn of a crumple-horned snorkack. Explosive.

You're like a bottle of Skele-Gro: growing me a bone.

Why don't I make like Salazar and Slyther inside of you?

I can be your house elf. I'll do whatever you want and I don't need any clothes.

Why don't you come tame my dragon?

I don't know a thing about Merlin's pants, but I'd love to get into yours!

You don't have to worry about me, I've been tested for Hogwarts, if you know what I mean.

Engorgio! Oh wait I don't need magic to enlarge this!

Did you say "Wingardium Leviosa"? Cause you've got me rising, baby.

Would you like a butterbeer? It's a portkey. Next thing you know we'll be back at my place.