If you have known me for a while you would immediately knew I would totally go with Gale.
I mean look at these too, THEYRE SO CUTE TOGETHER >///////<!!!! It's like a bad boy falls in love with the bookworm of the school that has had a crush on him since the first time she had to help him with his studies. Actually I'm pretty sure that's how their story would be if they were in a regular school anime. But besides that they are just super cute and sweet with each other and those times where Gajeel turns into a tsundere, it's funny and cute.