|Answer 1||It is heavily hinted, but not yet confirmed.|
|Answer 2||Well, in the previous chapters and episodes, they did show some kind of care for each other. Like Levy trusting and helping Gajeel when her partners are "bullying" him and Gajeel saving Levy from Laxus.|
|Answer 3||Although neither of them have made any romantic gestures to one another, in slightly recent chapters (210-212), it was implied that Levy may hold feelings for Gajeel. In chapter 210, Levy showed frustrationg that Gajeel was focused on fighting and not showing any interest in her "You keep talking about Fighting everyone! And never... care about me..." This implies she wants his attention, since when Gajeel responds for her to "become strong enough to fight sufficently against [him]" she becomes angry and runs off.
This, along with other hints: the light blushing when Gajeel says "don't leave my side", the 'heart' that is present in the word 'IRON' she conjures up for him to eat... This all heavily hint that Levy has feelings for Gajeel, her panic when returning and running ahead to an unconscious Gajeel (even though Juvia is also present and has known him longer and yet it's Levy who runs to his aid while Juvia and Erza remain aside) supports this.
As for Gajeel returning those 'feelings,' as of now it's clear he's fond of Levy as seen from his light teasing (such as ruffling her hair in a font gesture), and although he hasn't given any hints as strong as Levy's, it can be assumed that since he went after her when she ran away from him in chapter 210, and was also the one in the first place to offer to be her partner and "make her big" - a possible way of him trying to help her gain confidence. There is also evidence to possible feelings for Levy upon telling her that she shouldn't strain herself so much trying to carry him back to camp upon his collapse after defeating Yomazu and Kawazu of Grimoire Heart.
There is further hinting during a filler episode of the anime in which Lucy, Natsu, Erza, and Gray must attend a fancy dress party, which requires that they learn to ballroom dance (this inevitably leads to the entire guild joining in and dancing with one another). Though he is standing next to Levy, Gajeel states without any prompting that he refuses to dance, at which point Levy points out, with exasperation, that no one asked. As per usual, Jet and Droy begin to ask Levy simultaneously to dance with them, quickly dissolving into an argument. Before they can act, however, Gajeel interrupts them by suddenly dancing with Levy --albeit with a strained expression, stating "I guess I have no choice if you're going to be that way about it..." giving the impression that his previous statement was false (particularly since it would appear he already knows how to waltz). Levy, however, said nothing to spur his actions and goes so far as to say so, so it can easily be inferred that Gajeel feels possessive towards Levy, particularly when involving other male members of the guild.
Future chapters will have to be awaited to see how their relationship progresses, but as of now, it seems to be hinted.
|Answer 4||The person above pointed out most things about their relationship but I'd like to add one more thing. I think it's worthy of note that both Jet and Droy, two of the people closest to Levy and who have known her since childhood, have expressed that they believe Levy has a crush on Gajeel to the point that they feel they no longer have a chance with her (not that they did from get-go either).|
|Answer 1||I would also like to add that as the story has progressed their feelings have continued to grow, this can be seen in the cover art for chapters 213 and 319.|