How Can I Repair a Vintage, Art Deco Cigarette Lighter by Masai?

I have a vintage black panther art deco cigerette lighter, made by Masai in Modern Japan. So maybe around 1950?

Anyway, it sparks, but the fuel - butane - that I put in it leaks out. How can I repair this lighter? It looks like it attached inside the panther's head. I don't know how to pull the tank out.

Is this lighter even repairable?