Elfman Strauss is a prominent mage of the Fairy Tail guild and the middle sibling of the Strauss family, positioned between his older sister Mirajane and his younger sister Lisanna. Physically, he is one of the most imposing members of the guild, standing as a very large and muscular young man with tan-colored skin, long white hair styled into upward, wavy spikes, and a rectangular face marked by a distinctive stitched scar running down the right side and crossing his right eye. His black Fairy Tail stamp is located on the left side of his neck. His typical attire often reflects a Japanese-inspired aesthetic, consisting of a dark blue high-collared jacket with large kanji on the back, loose matching pants, and traditional geta sandals, though this outfit is frequently damaged during his magical transformations.

Before the tragic incident that defined his youth, Elfman was a notably shy and weak individual, with his primary talent being cooking. He possessed a caring and kind nature that was often underappreciated by many in the guild, though it proved invaluable when he helped his younger sister Lisanna and a young Natsu Dragneel look after a mysterious egg that would eventually hatch into Happy the Exceed. This gentle personality was radically altered following a catastrophic mission with his sisters where he attempted a Full-Body Take Over. He lost control of the beast's power and, in his rampage, struck Lisanna, an event that was initially believed to have caused her death. This trauma filled him with profound guilt and caused his heart to lock shut, reshaping his entire personality. Determined to become strong enough to protect his remaining sister, Mirajane, he transformed into a strong-willed and proud individual who is intensely self-conscious about his own manliness.

In the present day, Elfman considers himself a proud powerhouse of Fairy Tail and frequently prefaces his statements with phrases about being a "real man," using this concept as both a self-proclaimed image and a guiding principle for the behavior of others. He is known for spouting speeches about manhood and will harshly scold his comrades for failing to show what he considers proper masculine pride, as when he reprimanded Jet and Droy for putting their teammate Levy in danger. Despite this huge and often boisterous ego, he remains deeply kind, loving, and fiercely protective of his sisters and guild allies, going to great lengths to keep them safe from any danger, even threatening opponents much more powerful than himself. He is also emotionally vulnerable and can be moved to tears when his strength is questioned, a trait that contrasts sharply with his tough-guy exterior.

Elfman's magic is a specific variant of Take Over known as Beast Soul, which allows him to record and seal the power of monsters he has encountered or touched, transforming parts of his body or his entire form into those creatures. Initially, due to the trauma of losing control, he could only perform Partial Take Over, transforming just his right arm, which earned him the epithet "Beast Arm Elfman". He has access to several Beast Arm forms, each providing different benefits in combat, including the reptilian Scale Bull, the furry Bear, the metallic Iron Bull, the earthen Stone Bull, and the sharpened Jet Black Sword form he acquired by taking over an enemy's attack. When his sister Mirajane found herself in danger during the guild's conflict with Phantom Lord, Elfman finally managed to overcome his psychological block and achieve a controlled Full-Body Take Over. His primary full-body transformation is known simply as Beast Soul, turning him into a towering, dark red-furred creature with horns and sharp claws, described as the "King of monsters". This form dramatically increases his physical strength, speed, agility, and sense of smell, allowing him to battle and defeat extremely powerful opponents.

Family anchors most of Elfman's key relationships. He is fiercely protective of both Mirajane and Lisanna, often fighting alongside them as part of the "Take Over Siblings". His bond with his fellow guildmates, including Natsu, Gray, Erza, and Laxus, runs deep, and he has clashed with numerous foes to defend the guild's honor, including the dark guild Phantom Lord and the demons of Tartaros. One notable relationship that develops over the course of the story is a comedic yet genuine romance with Evergreen of the Thunder Legion, which blossoms after they fight side by side against the Grimoire Heart guild.

Elfman's growth unfolds across several major story arcs. The Phantom Lord arc marks his first successful, controlled Full-Body Take Over in years, used to save Mirajane. During the Battle of Fairy Tail arc, he stands against Laxus Dreyar's faction and bonds with Evergreen after their joint victory. On Tenrou Island, he fully restores his mastery over his magic, unleashing the Beast King against powerful enemies to protect his comrades. His defining moment arrives in the Tartaros arc when the Etherious Seilah seizes control of his body, forcing him into a desperate internal struggle. With help from his sister Lisanna, who had been revealed to be alive and living in the parallel world of Edolas, he breaks free from the demon's control, turns the Beast King form against Seilah, and saves Mirajane from certain death. Through each trial, Elfman learns that true strength lies not simply in physical might or magical power, but in the willingness to protect the people he calls family, a lesson that gradually tempers his guilt-driven recklessness with genuine emotional honesty.