Kaede, who is often called Maple, is a female unique monster initially encountered as a Poison Spider in the world of "Possibly the Greatest Alchemist of All Time". She becomes the first monster tamed by the protagonist, Iruma Takumi, after he finds her injured in the Forest of Gaia and heals her. This event forges a deep and lasting bond between them, with Kaede considering herself his familiar.

In terms of personality, Kaede is playful and can be quite lazy, yet she takes genuine pride in being helpful when the situation demands it. She acts very much like a spoiled child, wearing her heart on her sleeve and openly adoring Takumi for his kindness, often boasting about his best qualities to others. Despite being a spider, a creature many find frightening, her endearing and cute demeanor tends to attract people to her. One of her less convenient habits is spinning large webs in any area where she feels safe and comfortable, which frequently causes trouble for Takumi.

Kaede’s role in the story is intrinsically linked to her evolution and her contributions to Takumi’s household. Initially, she is a valuable source of silk, which is used for crafting and sewing. As she grows, she becomes a vital member of Takumi's group, known as the Wings of Nolyn, applying her abilities to support their shared objectives. Her skills as a seamstress are particularly notable, and she works alongside Maria to create the clothing for the entire household.

Her key relationships are centered around her master and her found family. Her attachment to Takumi, who saved her life, is the most significant, and she constantly seeks his praise. She develops a sisterly bond with Maria, another member of Takumi's household, and the two are often seen making clothes together from Kaede’s silk. She is also fond of Bogar, appreciating his caring nature and his role as a family man. Conversely, she dislikes Riell, who tends to harass her.

Kaede undergoes significant development, primarily through physical evolution. After living with Takumi in Bord village and later in the city of Bolton, she evolves from a Poison Spider into a larger Killer Spider. Her most dramatic change occurs during a goblin subjugation quest, where she evolves into an Arachne. In this form, her lower body remains that of a large spider, but her colors invert to a predominantly white body with black patterns. From the waist up, she gains the upper body of a small child with chest-length white hair, and her eight eyes transform so that two become humanoid. This evolution is a major milestone, as it grants her the ability to speak verbally with others, ending her reliance on telepathy to communicate with only Takumi. She also later adopts a Drake Horse, which evolves into the Dragon Horse Camellia.

Her notable abilities are closely tied to her nature as a spider monster. She is a talented seamstress who produces high-quality silk for crafting clothing and other items. In her earlier forms, she uses standard spider abilities such as web spinning and poison attacks. As an Arachne, she retains her silk production but gains human-like intelligence, speech, and a more formidable combat presence, combining her monstrous origins with a new, more humanoid form.