Yeah, to be honest if you're wanting to date ladies then I'd skip Japan altogether and just come here. Save your money because you'll need all of it here. Actually there are Korean and Japanese ladies here anyway, as well as Chinese girls learning Japanese.
What am I doing here? Well I'm doing a Mandarin Chinese course. Most Universities in China run them. They're mainly intended for students who want to get their Mandarin up to speed before doing a Chinese taught degree here, or for exchange students to come here as part of their studies in the US or any other country.
My course is around 15 hours a week but you can do extras like Cantonese, kung-fu, calligraphy and I've signed up for an intercultural communications module. Also they do a few trips out to visit factories and generally make the most of your being here.
A year's tuition costs 17200RMB but there are a few extras like visas, medicals, insurance, books etc. However, you can eat VERY cheaply on campus.
Also you can get a room from 1000RMB a month if you don't mind sharing a room or living somewhere basic.
How much more you spend depends on how much you get lured by the bright lights of downtown's clubs and bars etc. etc. Stay away from anywhere the expats go and you'll be able to live cheaply though.
My course runs indefinitely. They run 8 levels of class here though (beginner to advanced). I'll also see if I can do the HSK exams.
Go here for an overview of courses in China:
http://www.cucas.edu.cn/
My classes start tomorrow, so no word on how good the teachers are etc. etc. Also for purists then Cantonese speaking Guangzhou isn't the best place to study - Wuhan or Beijing would be better.
Bear in mind that these courses are taught IN CHINESE - there could be students from 20+ countries in your class, and the only common language you might be able to speak will be Chinese! What better way to learn?
It's possible to learn Chinese. The hardest part is pronunciation. Grammar is very easy, with no tenses, plurals or masculine/feminine forms like in French. Reading can be mastered as well - learn just 150 characters and you can figure out many street signs, menus etc.
Note that courses rarely teach writing - it's exceedingly hard to learn that later in life although typing it is very easy if you can read characters and remember the pinyin for them.
As to University life, well if you're a younger guy you'll fit in really well here. You'll make friends for life here. I'm a little old to be a regular student (and too unfit to join the sports teams), but my last job was in a University, and I'm putting some seriously impressive meat on my resume by experiencing life in a Chinese University. I'm also looking forward to drinking Chinese guys under the table - that's one sport us Western guys can win here.
As for other Asian countries, well Japan is dazzling but you'd need 2+ years to make it with Japanese women - and many foreigners go there and never find a girlfriend.
Vietnamese women are really beautiful but hardly any of them speak English. Also this is frontier country, and I imagine it's like the rough bits of this city, but with more motorcycles.
As for China, well it's noisy, chaotic and an amazing place to experience.