The cup is using Japanese letters that look somewhat like English letters to spell "Soul of Coffee". The comment is how those letters are read in Japanese.
All us former or present weebs that once learned Hiragana, Katakana, maybe 5 words and phrases, and basically nothing else, understand. (And the people actually speaking Japanese, too)
Oh, back then I totally also used.... some websites I found on google. And, uhm.... I think I remember printing out a torrented professional Japanese handbook, making a fancy folder to put it in and then.... never actually using it. :D
As you can see, teenage/young adult me was very realistic and very committed!
Reminds me of probably the most pretentious thing I ever did: as a teenager in the late 90s, I tried to learn Russian in order to read Tolstoy and Dostoyevsky in the original 😆