Thread:MMYP999/@comment-27109830-20190720105636/@comment-27416494-20191019143337

They're both hot-blooded sons of previous protagonists from their series who've largely grown to resent their fathers, whether it was because of John Morris's refusal to teach Jonathan to use the Vampire Killer, or Ky Kise's inability to attend to his son over his royal duties as a king. Jontahan and Sin would go on to spend their lives as career vampire/bounty hunters until the events of the present day, when they'd eventually manage to get over their grudges against their fathers after learning the truths of their respective situations. They also happen to be distantly related to the main characters of their series in general, as the Morris bloodline is loosely connected to the Belmonts, and Sol Badguy himself is actually Sin's grandfather.