Manga by author 돗가비 - Status ongoing

.[If I can't have him, I wish nobody could. If only my sister could disappear...!]Felix, who fell in love with his sister's fianc, Julian, knows she doesn't love him, but watching them from afar pains him. Felix, who wants to stay by Julian's side, gets a chance on the day of the wedding announcement.? a possessive desire for Julian. Is it obsession? Or is it love?