Can it be a platonic friendship if theres flirting involved?

Ive become friends with a guy in work who has a gf. I dont see anything but friendship at the moment but he does flirt with me and i find myself flirting with him even though i dont flirt in general. He is generally flirty with every girl but its like when i go in his office hell kick me in a jokey way to let me know hes there and when we go on work nights out hes hugging me and the other gals