Wave

Wave is a former member of the Demon Army and a former Demon General. He has romantic feelings for Sidero.

Due to the large amount of time he spent at sea in the human world, he is fairly unaware of the crime-riddled Ente Isla and corruption within the Land. He is very close to his mother and very well respected in his home village.

Appearance
Wave is a fairly muscular young man of above average height with short dark blue hair and eyes. He also has a cowlick. He wears a blue leather jacket and a red scarf with an anchor on it. The scarf is said to be his symbol of justice. Under that is a white shirt with a single blue line down the middle. He also wears a pair of grey jeans with a belt and dark blue boots. He carries his Teigu on his back most of the time.

Personality
He keeps his beliefs close to heart, such as duty to his country and cheering up a girl when she's sad. He is a true navy man at heart and loves everything to do with the ocean. He is shown to be level-headed and easy-going in his free time and has a desire to be useful to his friends.

He is shown to get along well with most of his comrades, excluding Lucifer. Despite constantly finding Bols' choice of attire very strange and wondering how a man of that sort is the only married member of the Demon Army, he is on very good terms with him and seems to think highly of him. He constantly tried to cheer up others, which usually fails and causes him to end up being cheered up by Sidero. Following the death of Bols and Sidero's admission of her fear being discarded, Wave seems to have grown extremely protective of the latter, showing his closeness to the two of them.

Lucifer himself has admitted that Wave, despite his own willingness to kill him if it comes to it, isn't evil, in fact he seems almost moral, a thing sorely lacking in those usually affiliated to the Demon Army.

Demon Army
Shirahime: Sidero is the member of the Demon Army that Wave has the closest relationship with. The two get along well and are often seen together. Over time they develop a strong and caring bond. She even tells him about her fear of being disposed of by the Demon Army after she's weakened by injuries. He has silently declared that he'll protect her, and has done so several times. An example being taking a hit for her that would've killed her otherwise. He is also very protective of Sidero and attacks Syura when the latter attempted to take Sidero as his new toy. Over the course of the series, Wave develops romantic feelings for Sidero, which she doesn't return. He cares for her greatly, most notably about her health.

Hanzo Urushihara: While they only met briefly, Wave immediately warmed up to Lucifer and liked him. He saw Lucifer as the only other "normal" member of the Demon Army and he saw a lot of similarities between them. Wave and Lucifer remained on friendly terms, complimenting each other's strength and resolve, and even admitted that they trusted each other despite being enemies because of their affections for Sidero.

Esdeath: He respected his leader greatly but was also terrified of her and her harsh punishment for failure. Esdeath has noted that she regarded Wave as both incredibly strong and very talented, and that he had almost perfected his strength. Wave appears to have great faith in Esdeath, and was relieved to have her back when she returned to the demon army.

Bols: Though initially frightened by Bols' outward appearance, Wave eventually formed a strong bond with Bols, and saw the man's gentle nature behind his mask. Wave was strongly affected by Bols' death and was later seen bringing flowers to his grave, as well as offering help to his family. Overall, Bols' death deeply affected Wave. It caused him to swear to avenge Bols during one of Heaven's attacks and he later attacked Syura, partially for killing Bols' family.

Seryu Ubiquitous: Initially puzzled by Seryu's cheerfulness, Wave at first befriended her and was concerned enough about her well-being to want to comfort her after Dr. Stylish's death. However, he became more distant towards her after the latter revealed her psychotic nature. It was Seryu's psychotic nature that made Wave question the true nature of the Army he served. However, he still cared for her and wanted to avenge her death at the hands of Heaven, along with the deaths of Koro and Bols.

Dr. Stylish: Initially frightened by his effeminate nature, he warmed up to the scientist enough to consider him a comrade.

Heaven
Syura: Wave openly detested Syura, mainly due to Heaven's brutal methods during investigations, and Syura's abuse of his privileges as the son of the Prime Minister. He was further provoked by Syura when Heaven tortured and killed the family of Bols, a deceased demon. When Syura harassed Sidero and wanted to claim her as his new toy, the two men fought. Wave defeated Syura in hand-to-hand combat and humiliated him. While Syura wanted to kill him afterwards, he wasn't allowed to do so because Wave was a member of the Demon Army.

History
Wave was born and raised at the country side probably near the sea. Wave joined the navy due to the help of certain someone whom he respected. At some point in his life he come to possess the Grand Chariot Teigu. After some time he was called from his village in order to join a special army that was requested by Esdeath. While his mother was worried about him leaving his father told him to give the enemy hell.

When he first arrived at the meeting room for his new group, he first encountered Bols, who stared at him awkwardly until the rest of the crew showed up. He quickly took a liking to Run, who was in his opinion the only other "normal" person present. After Esdeath 'played' with Wave and the rest of the group a party was held and the sea food he brought was used for it.

In order to find a suitable wielder for the Teigu that was retrieved from Heaven, a tournament was held and Wave acted as the announcer of it.

Later, the Demon Army is ordered to eliminate a group of bandits. Wave assists his comrades in their attack on the hideout, while Sidero and Lucifer watch from afar.

Equipment and Skills
Wave wields the Armor type Teigu, "Grand Chariot," which is a more attack oriented version of Incursio. It is unknown which Teigu is stronger, as Lucifer was unwilling to fight Wave. The Teigu increases his strength and speed as well as giving him the ability to fly. However, his Teigu is unable to turn invisible as opposed to Incursio. He has a technique named "Grand Fall" which is a powerful kick that Maou noted could have killed him if he did not block it. While his Teigu is engaged he is capable of taking on Sidero, Lubbock, and Mine simultaneously and was referred to as a force of nature by them.

Wave is also a formidable swordsman and uses his sword more than his Teigu. Esdeath has said that his strength is perfect, thanks to having a good teacher. He is skilled in hand-to-hand combat as well, and defeated Syura in an unarmed duel despite it being the specialty of the latter.

Wave himself states his skill to be at least on par with Lucifer, although the two have not yet had a proper battle. While he is aware of dangerous creatures inhabiting the ocean, he was caught off guard by creatures living in the mountains, likely due to his lack of first hand experience in dealing with them at the time.

It is also worth noting that he is the only one in the series who managed to land a clean, direct and powerful blow to Sidero, though it is only because Sidero was not fully focused into the fight as she stated.

Trivia

 * Wave's birthday is written to be March 16.
 * He is parallel to Lucifer in many ways.
 * His name is a reference to his work and likes, similar to Lucifer.
 * For instance, he sees himself as the only level-headed and normal person in a group of eccentric characters, something that Lucifer empathizes with, stating "I know what you mean."
 * Wave is the first individual to wield two Teigus.