Slotos

Slotos (スロトス) is a mid-ranking devil who serves Nacht Faust, the vice-captain of the Clover Kingdom's Black Bull squad of the Magic Knights.

Appearance
As a devil familiar, Slotos appears as a small, dark-colored figure with horns, wings, and a tail.

When merged with Shadow Magic, Slotos appears as a large, black figure with black horns and a purple, horse-shaped mask.

Biography
After Nacht Faust interrupts a captains meeting, he summons four masked beasts to stop the captains from attacking him, with Slotos holding back Jack the Ripper. After Julius Novachrono vouches for Nacht, the captains relax and the beasts disappear.

When Asta defeats Liebe and insists on forming a contract of equals with the devil, Slotos appears alongside Gimodelo and the other devils. The devils cling to Nacht's head and shoulders as Nacht enters the circle and compliments Asta's choice. Slotos and the other devils disappear when Gimodelo merges with Nacht to continue Asta and Liebe's training.

After Nacht admits defeat, he leaves behind Gimodelo to continue Asta and Liebe's training since their union needs more work. The devil is terrified of the possibly lethal attack again, and Nacht's other devils comfort Gimodelo.

While fighting Dante Zogratis, Nacht summons Slotos and merges with the devil in order to withstand the increased gravity and to buy time for Jack the Ripper's Slash Magic to adapt. When the roots of the Tree of Qliphoth suddenly grow, Nacht switches to Plumede.

After the first gate to the underworld opens, two highest-ranking devils—Lilith and Nahamah—appear in Dante's chamber, so Nacht pulls them into another part of the castle and traps them in his Dark Prison Hunting Ground. Nacht dodges around the devils' attacks and positions himself behind Nahamah. He switches to Slotos and kicks Nahamah's back, but his leg passes through the devil's torso as it turns into fire. Nahamah then destroys Nacht's left shield, so Nacht returns to focusing on dodging.

After the Black Bull base smashes through the castle to the ritual chamber, Nacht and his devils watch from above as the other Black Bulls defeat Moris Libardirt and Yami Sukehiro wakes up. Shortly after, the second gate to the underworld opens, and Lucifero partially manifests through the combined bodies of the devils from the first and second levels. Nacht then merges with Slotos in order to withstand Lucifero's gravity.

Abilities

 * Toughness (剛健): When Slotos assimilates with Nacht via Unite Mode: Equus, Nacht's physical resilience is greatly enhanced, allowing him to withstand and move in immense gravity.