It's tough to beat a credit card's convenience, so I felt naked and demoted after moving to Japan and encountering a sea of rejection when trying to apply for a local credit card. True...I could use my US credit card, but that weak dollar / strong yen exchange rate right now would obliterate my US savings account. In addition, overseas card transactions are often denied by the vendor or credit card company or both; and sending money home to pay the bill effectively strips the credit card of its intrinsic convenience.
Damn, I wanted a local card. But at the same time I understood their reluctance to grant me one. I'm a gaijin, and everybody knows that we're the ones that commit all the crimes here. I could easily go on a crazy "Brewster's Millions" shopping spree and skip town. While jobless irresponsible American me managed to get a decent credit card as a college student, responsibly-employed living-in-Japan me failed time and time again.
Don't bother with Shinsei.
While it's true that Shinsei Bank is known as the most gaijin-friendly of Japan's banks, the same cannot be said of their credit card division because it's outsourced to another firm (called "Aplus?"). Following heretical advice from both foreign and Japanese friends, I applied numerous times over a period of a few years. Each time I promptly received a polite, yet curt letter of rejection. I was surprised since my other foreigner friends had previously found success--flashing their shiny, envy-inducing pantone cards in my face. But since the "Lehman Shock," those days of freely granting credit to non-permanent residents was over. It was fun while it lasted.
Apply for a card associated with a bill you already pay.
Dejected and depressed, I traversed other avenues desperately seeking one that would grant the blue-eyed devil a smidgen of credit. I finally found success with a card associated with my utility company 東京電力 (Tepco). The only catch was that from then on I had to pay the power bill via the new credit card. I didn't mind that in the least since it continued to be automatic and even rewarded me with a bonus discount. Ya gotta love those point cards!
Upgrade your visa.
I can't say with any certainty what it was that got my application approved. Maybe it was my boyish charm and Colgate smile. All I know is that Tepco is my new best friend (next to Japanese gum tape). I did apply for credit cards more aggressively after securing a spousal visa thinking that would guarantee approval. I was wrong. I was still rejected by other companies. I was even rejected by American Express despite my American citizenship. What a bunch of jerks. I should sue for false advertising.
The majority of credit card-holding foreigners likely have permanent residence (永住権) as this is often cited as the door-opening hurtle to a full, convenient life in Japan free of midnight deportations and dramatic scenes at the embassies. If you have lived in Japan for a while now, plan to stay, are not (I repeat, NOT) committing crimes, are married to a Japanese citizen, and/or have children, apply for PR. Looking at some of my douchebag friends, it's not as hard to get as you may think.
I know I'm going to. Then maybe I can improve my crappy credit limit. Best of luck to you, fellow foreigner!