Major Alex Louis Armstrong, the Strong Arm Alchemist, was born into an elite family of alchemists and has mastered his family's techniques. Members of his family have, in the past, filled the highest military and political positions in the state. He acquired his alchemy titles for his skill of using arm strength in his alchemy. All though he may look intimidating, he is really friendly and (overly)affectionate, and often stays behind or risks his life for the safety of others. He also has a tendency to show off techniques passed down to him to his enemies, and make them feel somewhat awkward during a battle. The scion of the illustrious Armstrong family, Alex is a remarkably caring commander and friend as well as an invaluably skilled ally to Colonel Roy Mustang and Edward Elric.

Tatsumi Oga is the main protagonist in the Beelzebub series, first introduced as a strong fighter, beating up some fellow class mates and then making them bow down to him because they had attacked him in his sleep. He was picked to become Beelzebub's parent as he possessed the qualities of the ideal parent for the future Demon Lord: strong, arrogant, and thinks-nothing-of-fellow-man. In addition to the aforementioned attributes, Oga also seems to take pleasure in tormenting others.As the series continues, it should be noted that the trials Oga has faced and the new friends he has gained has altered his personality somewhat. For example, when the Rokkisei called out Ishiyama to meet them on the rooftop, he initially came alone. But later on when Himekawa, Kunieda, and Natsume soon arrived, Oga smiled knowing that they have his back. Though he retains his love for his cruelty. (Source: Wikipedia)