Seam, (Pronounced Shawm) is resembling of a raggedy plush cat with dull purple fur, brown cloakish clothes, and a fuzzy orange collar around their neck. They have a black nose, several patches on their body and head. While their left eye socket is empty, their right eye is an orange button. An orange scar or rip runs down their button eye to their cheek. Their mouth is orange on the inside, with another rip. They no longer have a tail, suggesting it having been ripped off by "by cruel and loving hands." Seam is initially cynical and nihilistic, believing the "end of the world" to be nigh, and the actions of the heroes to be futile. Despite this, they maintain a cheerful attitude, helping out the heroes in good faith. They have a deep, soft, empowering voice. They root for the party, and provide them with items, as well as information. Some of this information is about the court jester, Jevil, giving hintd as to how they must unlock his prison. They also prepare them tea. As the heroes progress, Seam appears to grow more hopeful. Seam appears as highly self deprecating— claiming that neither Light nor Dark hold a future for a Darkner in their condition, calling their wares old junk, and telling the heroes they will find little reason to visit, as they will find stronger items elsewhere. Seam was previously the court magician in card castle, working underneath the four Kings, alongside their subordinate Jevil, the court jester. They were suggested to be close. However, one day, Jevil met a "strange someone", (hinted to be gaster or friend) and his personality began to change. soon, Jevil went mad, and Seam was forced by the four kings to lock him away in a prison, devoid of light, constantly moving with nothing but his own voice. Seam claims that Jevil's "strange words" have made their view of the world "darker, yet darker." ever since. They can perform magic, being a mage. They often win in card games and that of the like, stating the only one who matching their level being the jester.

The (former) court jester. Jevil is a short imp with a purplish-gray round face and pointed ears. His face has black vertical lines across his eyes, which have black sclerae and small yellow pupils. Jevil's wide mouth has sharp, yellow teeth, and a long purple snake-like, or during some of his attacks. His head appears to be connected to his body via a coil spring, akin to a jack-in-the-box, which is only exposed when attacked. Jevil has a purple tail, with its end split. It is usually curled, resembling a devil. On Jevil's head is a purple and black harlequin jester hat, with a small yellow bell on each end. Around his neck is a lime green and yellow ruff with a black cape. Jevil wears a black-sleeved, purple shirt with black triangle patterns on the center and stripes on the side, purple mittens, black trousers and black shoes with a green toe box. His outfit is very ruffly. Prior to losing his mind, Jevil is implied to have had a humorous attitude and was on par on playing games with his companion, Seam. Following his descent into madness, Jevil retains his eccentricity and vitality. He has a sadistic sense of entertainment, perceiving an encounter with the party as a "GAME", which is seemingly the reason he was locked away. However, Jevil also has a cynical worldview, as he considers everyone else trapped instead, as he is one who has seen the true way of the world. Jevil usually repeats words in a sentence, a speech disorder known as Palilalia. For example, "FIND THE KEY, AND I'LL LET YOU BE FREE, FREE." He also often rhymes. Some time before Kris and Susie entered the Dark World, Jevil worked as the court jester alongside Seam, who worked as the court magician. One day, however, Jevil came across a "strange someone", and his personality shifted permanently. According to Seam, Jevil "started saying bizarre things that didn't completely make sense - But didn't completely not make sense, either." Jevil managed to convince King that the Knight, and the Dark Fountain it would create, could help him rise to power. Eventually, Jevil started viewing the world as a game, and everyone else as its participants. Because of this, Seam was forced by King and the three Former Kings to lock Jevil away underneath Card Castle.