You and Harry flirt with each other almost all the time, even holding hands for fun.

It's winter, your hands are freezing and you see Harry, you slowly walk up to him from behind and put your cold hands under his shirt...

He is startled, takes your hands out and turns to you, when he sees you he grins and slowly puts your hands back under his shirt...

"Why do you have such cold hands darling?" He asks you, holding your hands under his shirt.