A thought came suddenly. At first I only thought about Suzuya Juuzou from Tokyo Ghoul then I thought about Kotone (FeMC Persona 3).
Kotone hairpin is XXII which is a Roman numeral. If we change it to Arabic numerals (the numbers we usually use every day) then it is the 22nd number. Considering that Persona uses a system related to Tarot, the XXII (22) Arcana in the tarot deck is The Fool, which is the Arcana of Kotone and the modern version persona protagonists (3, 4, and 5). In the 22 Major Arcana system, the Fool card is usually placed as number 0 (the beginning), but in some historical traditions, The Fool is numbered 22 as the conclusion of a spiritual journey.
Meanwhile, early Suzuya Juuzou has hairpins of the Roman numeral XIII (the number 13). In Tarot, it is the Death Arcana that represents a psychological shift where shedding the old (such as bad habits, relationships, or outdated perspectives) is necessary to make way for personal evolution and rebirth. And as we all probably already knew, the number 13 is considered an unlucky or cursed number, or a number that brings misfortune. Fun fact, it is considered a cursed number especially because of stories in religion and folklore. In Christianity, Judas Iscariot was the 13th guest present at the Last Supper and betrayed Jesus. Additionally, in Norse Mythology, the trickster god Loki was the 13th guest who triggered chaos that killed the god of light.
You can also see that the hairclips of Suzuya in Tokyo Ghoul:RE changed. It became XX. The Roman numeral XX is 20. The number 20 itself has the symbolism of perfect waiting, the beginning of a new spiritual journey, and relational balance. Spiritually, this number represents the end of a life cycle and a transition toward a phase of greater potential. The number 20 represents the end of the second cycle (twice the power of the vibration of ten). In Tarot, the number 20 is associated with the Judgement card, which means resurrection and the principle of what you sow is what you reap. Meanwhile, in Japanese culture, there is a special term, namely hatachi (二十歳), to mark the 20th birthday, which becomes the age of legal adulthood and privileges for a person.
Though maybe the mangaka probably only gave Suzuya that accessories because of his some sort of hobby on sewing his own skin, Suzuya himself looks like a doll in a way because of it, dunno if that hairclip part is intentional or not, either ways it's still a cool detail, same for Kotone.




















