Laxus Dreyar. He was once a douchey guy, with arrogance and an ego that didn't fit his head, but now? Honestly, he could still be the same. He's trying, trying so desperately to be more open with the guild and start to shock less people, but that's not the easiest when it's a habit. It's like asking Gray to stop stripping, and you only give him a few months to stop something he's been doing his whole life...
Even though he hates to admit it, he needs help, especially if his Grandpa expects him to take over "for real" when he finally gets serious.
A perfect person to help him would have to be:
& D) A Wizard who can defend him or herself
A, he needs to learn to cooperate with others. B, showing his feelings isn't exactly a strong point. C, if they are all rainbow and sunshine, telling him to just be happy, that clearly wont work. D, if he blows up on this person, and he knows he will, they need to be able to take a few hits and throw a few punches, or he's going to be even more of a outcast to the guild.
When he told his Grandpa all this after coming back, he honestly expected him to throw Mirajane out with him, or even that little girl that cowered behind trees at the sight of him, but no.
Instead, another blonde was forced into the deal, even though she disagreed with a passion, but Makarov wouldn't hear it.
"He's your family now, and It'll be a good experience for the both of you." Makarov chuckled heartily, ignoring the expression of absolute horror on her face, and the extreme discomfort of the other blond.