Having purchased a figuratively decorated enameled wall vase before Christmas for my daughter in Toronto, but not quite sure what I'd got, I headed for the home of Byron Monasmith in Tokyo's Shinanomachi.

"Ah," he said, perching tiny Taisho-era silver glasses on his nose and reaching for a reference book. "Benzai-ten, commonly known as Benten-sama, derived from the Hindu god Sarasvati, and the only female figure among Japan's seven gods of good luck. The goddess of water and music, she's usually depicted playing a 'biwa' (lute), as here."

I knew I'd gone to the right person.