Green Plaza Ladies Sauna?

So my Lonely Planet says that here, apart from using the sauna and bath facilities, women can "blissfully snooze away until morning trains begin running". But then I looked it up and another website said sleeping here was for men only. I'm confused? Can anyone clarify? Because I would like to stay there for one night when I visit Tokyo, and I'm female.

Thanks!

The Japanese website has details about the women-only facilities on floors 8 to 10.
See the photo at the bottom of the page for the sleeping room.
http://www.hgpshinjuku.jp/spa/info/index.html
Cost is 3,400 yen for up to 10 hours from 10pm.

That's incredibly helpful. :) Couldn't find that website by myself for some reason. Thank you so much for pointing me in the right direction!

Kelly,

I misinterpreted the website slightly, assuming that you had to pay 3,400 yen to stay there overnight, but if you check in before 10 pm, then it costs 2,800 yen - still for a stay of up to 10 hours. Note that you can't come and go freely once you have checked in.

You mean when you go in, and then you go out, you can't get back in? That's alright though, I just plan to go there, use the bathing facilities and sleep. And then leave, haha.

Anyway thanks for the info. :)