He looks very young but is actually an adult.
He has an ability called Full Counter, which allows him to tank an attack and then redirect it back at his opponent without the attack losing any potency (he also has some demon abilities, but it's a long story). Full EnjoymentMeet the calm Captain of the Seven Deadly Sins, the Dragon Sin of Wrath, Meliodas. He even comes with removable accessories. Fans of this anime will get a kick out of this officially licensed Meliodas The Seven Deadly Sins Wave 1 7-Inch Scale Action Figure! The Seven Deadly Sins Wave 1 Meliodas 7-Inch Scale Action Figure Ironically, Meliodas is the smallest one on the team but is arguably the strongest member.