Seviathan von Eldritch

Seviathan von Eldritch is a member of the von Eldritch family and Charlie's ex-boyfriend. He is a character in the Hazbin Hotel series.

Charlotte Magne
From what has been revealed, Seviathan and Charlie used to date. They were at least dating around the time of hell school.

Helsa von Eldritch
Helsa is Seviathan's sister. Aside from being blood-related, little is known about them. And given that Helsa and Charlie share an antagonistic relationship, it is unknown if Seviathan's romance with Charlie affected his and Helsa's.

Trivia

 * Charlie having an ex-boyfriend was first mentioned in Vivziepop's twitter. Pictures of Seviathan and his family can be seen with the Magne Family all over the hotel as the two families are of elite standing.
 * Sevianthan's name is a reference to Leviathan, a creature which takes the form of a sea serpent in the Hebrew Bible in the Book of Job, with "S" replacing the "L".
 * Before the offical name was announced, fans referred to him as Harold von Eldritch.