My brain has to be such a jumbled mess not to remember who Jelasis was, considering his presence in the story.
If, like me, you need a reminder: He's the second son of the Ignite ducal family, a concubine's bastard who was treated cruelly by his father and kept as insurance in case the firstborn died (chapter 7), was born with a demon inside of him and, while being part of Patricia's harem, is obsessed with Alicia, having been the one behind all known attacks on her so far (chapters 1+2, 9-11) and the handkiss mentioned, where he engraved the demonic sigil, happened in chapter 13.