Hunson Abadeer

Hunson Abadeer (a.k.a. the Lord of Evil) is Marceline's father and the ruler of the Nightosphere. He is a powerful, deathless demon who is full of chaotic evil. He also enjoys consuming the souls of others, but does not spend much time out of the Nightosphere.

He first appears in "It Came from the Nightosphere", wherein it is revealed that he has a shaky parent-to-teen relationship with his daughter. However, Hunson manages to reaffirm his love for Marceline just before being sent back into the Nightosphere. In "Memory of a Memory," Finn sees a flashback of him eating his daughter's French fries, an incident that caused a rift in their relationship and led to Marceline writing her "Fry Song." He reappears in "Daddy's Little Monster," trying to trick Marceline into taking over the Nightosphere. He appears again in "Marcy & Hunson," where Peppermint Butler summons him to Ooo to power up a new Night Sword for Finn, and he stays for a day to visit Marceline.

Personality
He is an embodiment of chaos and claims to be "completely evil" (these are later suggested to be effects of the Nightosphere amulet). He also shows appreciation for things he deems to be greatly evil; in "It Came from the Nightosphere," he comments that Gunter is the "most evil thing [he] has encountered" (foreshadowing Gunter's reveal as Orgalorg). Gunter, the Ice King, Jake and Finn were the only souls that were spared during his rampage through Ooo.

In addition, Hunson Abadeer is shown to be rational, cold and calculating. However, he is not totally emotionless, as he appears to be deeply moved by hearing his daughter's song. He confirmed that he loves Marceline, and that he was deeply sorry he ate her fries, never meaning to hurt her. This incident seems to have altered his personality, as in "Return to the Nightosphere," he is far less evil than before even with the Nightosphere amulet on, with the implication that this change was because of his previous interaction with Marceline. While he is markedly 'nicer' than before, he may only be so to Marceline, Finn and Jake. In "Daddy's Little Monster," he was quick to act hostile toward Jake before realising it was him.

He seems to have a twisted sense of humor. He threatens the lives of the Marauders by telling a joke and calls himself their "Mama." He also sings a song about "sucking up souls and stompin' on ants."