Ichiya Vandalay Kotobuki is a mage from the Blue Pegasus Guild, where he holds the position of ace and also serves as the leader of a team known as the Trimens, which consists of Hibiki Lates, Ren Akatsuki, and Eve Tearm. Despite his high rank and the respect he commands from his team, who call him aniki, or older brother, he is often mocked by others for his unusual appearance. He is a short, stout man with a large, rectangular face, a prominent flat nose that often shines, thick eyebrows, and orange hair. Even though he is only twenty-nine years old when first introduced, many characters mistakenly refer to him as an old man because of his peculiar features. Over time, his hairstyle changes, becoming longer and more unkempt after a seven-year timeskip, but his overall look remains largely the same.

Ichiya has a very distinct and flamboyant personality. He considers himself a great womanizer and is incredibly vain, genuinely believing he is handsome despite all evidence to the contrary. He has an obsessive love for perfumes and fragrance, which ties directly into his magical abilities. This fascination often manifests in invasive ways, as he frequently attempts to sniff the scent of women he finds attractive, most notably Erza Scarlet of Fairy Tail. He and Erza share an undisclosed history, and he constantly refers to her as "my honey," a gesture that is always met with visible disgust and physical violence from her. He has a verbal tic, often ending his sentences with the English word "men".

Despite his comedic cowardice and a tendency to try to flee from danger, Ichiya possesses a strong sense of loyalty and genuine courage when it truly matters. He often acts in a selfish or creepy manner, but he cares deeply for his friends and allies. He proved his dedication by spending seven years searching for the missing members of Fairy Tail after they vanished, showing a profound sense of friendship. He is also capable of defying higher authorities, such as the Magic Council, to help a friend in need, demonstrating that his character runs deeper than his silly exterior.

Throughout the story, Ichiya serves as a supporting ally to the main cast. He represents Blue Pegasus during the allied assault on the dark guild Oración Seis. While he is easily captured and tied up during this mission, he eventually breaks free and uses his magic to destroy a crucial part of the ancient weapon Nirvana, contributing significantly to the mission's success. He reappears during the Grand Magic Games arc and continues to aid Fairy Tail in later battles, including the war against the Alvarez Empire, where he plays a key role in defending the Fairy Tail guild hall from a powerful enemy assault.

His key relationships are defined by his interactions with the Fairy Tail guild. His one-sided infatuation with Erza Scarlet is a running gag, though she acknowledges his strength as a mage of the "well-to-do" sort. He shares a respectful bond with his own subordinates, the Trimens, as well as with other powerful mages like Jura Neekis. He also has a unique connection to his Edolas counterpart, an Exceed named Nichiya, whom he essentially adopts and brings into the Blue Pegasus guild.

Ichiya undergoes subtle but notable development. Initially presented as a purely comic relief character who is both vain and weak, he proves his worth through actions rather than words. His unwavering search for the Fairy Tail mages for seven years adds a layer of tragic loyalty to his persona. Later in the series, he demonstrates immense physical fortitude, surviving brutal attacks to protect others, which shifts his perception from a joke to a surprisingly resilient and reliable warrior. He evolves from a character who begs for his life to one who willingly sacrifices his body to shield his allies.

Ichiya relies on a unique form of magic known as Perfume Magic. He carries various vials of cologne and fragrance, each producing a different effect when inhaled. One of his most frequently used abilities is the Pain Relieving Perfume, which heals the wounds and injuries of those who smell it. He uses the Power Perfume to dramatically increase his muscle mass and physical strength, allowing him to shatter large objects or deliver powerful punches like the Smiling Smash. Other variations include the Fleet-Foot Perfume for increased speed, the Armpit Perfume which releases a repulsive stench to stun enemies, and the Thunder Perfume, which allows him to generate and manipulate lightning. He also created the Handsome Perfume, a banned magical item that infects people and forcibly turns their faces into a copy of his own, leading to a chaotic plague-like outbreak in the city of Magnolia. In addition to his magical abilities, Ichiya possesses a remarkable sense of smell, comparable to that of a Dragon Slayer, and is a capable hand-to-hand combatant when enhanced by his perfumes.