Victor's actually a Magnus Archives OC, so all his tattoos are a mix of directly symbolic of his Fear alignments, or vague vibe-based imagery :V the snake is his escaping his family/original fear but falling into a new one, it literally winds up his whole arm and ends wrapped around his shoulder-

-with an eye at the center! The sun + star + moon are tied into the muddy sense of spirituality he still has despite the trauma of his upbringing :0 the red line is honestly just aesthetic lol