Notes:

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List of nendoroid used for custom

Bowsette
Hair – Shinobu + Eri (for pony tail)
Arms – Shinobu
Body – Nendoroid more : wedding
Horns – Black gold saw
Crown – Koharu

Boosette
Hair – Shimakaze
Arms – Albedo
Upper torso – Warspite
Lower torso – Nendoroid more : wedding
Crown – Koharu
Ghost : Nendoroid more : Halloween