Solomon Demeter was the Captain of the 2nd Company of the Emperor's Children Space Marine Legion. Demeter was somewhat atypical for an officer of the Emperor's Children, being possessed of a steak of individualism and recklessness that made him stand out from his peers. During the dark days of the corruption of the legion, his individual nature, along with a twist of fortune, led to him becoming virtually the only senior officer of the legion not to succumb to the temptations of Slaanesh.
The very image of a Space Marine in appearance, Demeter's dark hair was shorn close to his scalp and his skin was tanned from the light of the several suns he had fought under. He was expressionate, with heavily animated features well-spaced across his face.
Confident in his own abilities and somewhat self-reliant, Solomon heavily customised his weapons until they met his satisfaction; every surface and working part of his Bolter was hand-finished, giving it a slightly better rate of fire than standard issue weapons and his chainsword had been altered to have a longer grip and blade, allowing it to be used as a two-handed weapon. The hilt was extensively crafted to resemble an eagle. He regularly checked and re-checked his equipment before battle, honouring his battle-gear with a fervour he sometimes wondered if bordered on the superstitious.
During the Cleansing of Laeran, Demeter found himself constantly hard-pressed and having to operate against the customary practices of the Emperor's Children, such as disparaging a helmet (which he disdained as useless, the Laer having broken the Astartes vox-codes and having weapons whose effectiveness rendered the protection a helmet offered highly negligible) right up to having to organise assaults hurriedly and without the optimum troop types. Despite the sheer lethality of the combat zone and the awkwardness of having to learn new ways of war on the fly, he found himself enjoying improvising his command. The experience made him something of a rogue; he learned to stop worrying so much about making the 'right' or 'correct' choice, so long as he made a 'good' choice. This way of thinking was not common or particularly approved within the Emperor's Children, and combined with his eagerness to fight, earned him the mild disapproval of some of his peers and even subordinates. He referred to his favourite tactic of leading a powerful, methodical but speedy frontal advance on the enemy as "going up the centre".
However, Demeter was a firm believer in the philosophy of his Legion and worked hard to both learn from his superiors and peers and to set a fine example to his men. Long a senior officer, he contributed his part to the tactical doctrines taught to initiate Emperor's Children. As a senior officer, he was a regular attendee to the Emperor's Children version of the warrior-lodge, the Brotherhood of the Phoenix, and had in fact been allowed to attend a meeting of the Luna Wolves warrior-lodge in the past, which he had enjoyed.
Often seen as particularly lucky due to managing to avoid what should have been certain death, Demeter miraculously survived a terrible crash-landing into the oceans of Laeran during the final battle of the campaign. As a result he missed being present in the Laer Temple when Fulgrim found the Laeran daemon weapon.
Demeter eventually recovered in time to lead his company in the assault of the Diasporex capital ship, and in fact captured the vessel. Normally this would have brought him great glory, but the changes taking place in the legion after the Cleansing of Laeran made this achievement not a politically wise one. Despite standing with his Primarch and his peers against the outnumbering Eldar forces of Craftworld Ulthwé, Demeter began to find himself marginalised within his Legion. This increased over time to the point where, during the pacification of Deep Orbital DS191, 2nd company was not supported by the 1st and 3rd companies as the battle-plan had laid out. Demeter and his company found themselves over-extended and in real danger of being cut off and destroyed. They were saved from this fate by the unplanned arrival of forces under the commands of Captains Saul Tarvitz and Lucius, two junior officers that Demeter had found himself associating more and more with as he was systematically frozen out by Legion high command.
Almost immediately afterwards the Isstvan III campaign began, and Demeter was assigned to the first drop, the one that would be betrayed. Badly wounded in the firestorm that followed the virus bombing, he missed the initial organisation of the loyalist survivors, and by the time he was able to fight, Captain Tarvitz had commanded the Emperor's Children survivors for many weeks. Demeter decided against taking field-command and instead fought where he was needed.
However, weakened in spirit as well as body, his self-belief and good fortune ran out when he was eventually betrayed and killed by the turncoat Captain Lucius, after being tricked into helping the swordsman slay loyalist marines. Despairing of his acts and of the fate of the future, Solomon Demeter died in the Precentor's Palace on Isstvan III.