Because they're so cute together. As what have Gemini said, Gray is somewhat interested in Lucy. They look pretty good together and Juvia is the one who likes Gray not him as he always ignores her. Lucy and Gray even hugged! D'aww!! :D
because they look good together and besides their a perfect together.......and because gray cant be with erza because she Любовь jellel...he cant be with juvia because she might Любовь lyon..
lucy cant be with natsu because he likes lisanna....she cant be with loke because he is lucy's spirit and i think he loves aries...
