Sin

Sinclair, otherwise known as Sin, is an interloper along with their older sister, Skylar. The two were stowaways on a ship as refugees and ended up in the Magic Tea Shop when they landed and escaped. With nowhere to call home, Satu quickly welcomed them in and they became like younger siblings to Fleur.

They're more the cynical brains to their older siblings, but they don't mind watching them have fun, as long as Skylar is happy. That's what drove Sin to try and escape their home country for, after all!