Arona can be extremely kind to anyone that somehow manages to become his friend. While it isn't too hard to become this man's friend. His attitude and ruthlessness in battle usual push people away. But once they become his friend, he'll treat that person not only as kind as possible, but with extreme loyalty, rushing into battle to protect them at every opportunity.
The black haired man is perfectly fine with making enemies with anyone who would dare to cross his path. Standing at a towering height of Six feet and Eight inches he doesn't believe many people would like to be enemies with him, but in these new worlds who knows? Someone out there might like the challenge. Arona is also fine with having a rival, someone who could keep trying to best him at every opportunity, or maybe even the other way around.
Arona doesn't have much going on with his life, besides working for his home and training to be even stronger. Leaving him with more than enough time to find a special "someone" in his life.
Anything else you can think of will fit here.. Frenemies, Master and student, all kinds of different things not covered by the three sections above. Feel free to leave any ideas below as well as leaving plot ideas here.