Sleep-in on bicycle touring ideas?

go ask the other churches + youre less likely to be raped

Yes you will be allowed. A Christian delegation came to speak to the Prophet Mohamed and they slept in the Mosque of Madina.

I doubt if you would be prohibited due to your nationality, although whatever faith you possess might be a problem. Some Imams might be more particular than others. You could of course fake it, but that would be an insult to your friend. I suggest asking your friend this question. Can you accompany him?

No pork eaters in mosques.

Non Muslims are allowed to go into mosques, just be clean and wear proper clothes ask the imam or someone in the mosque I think they would allow you to sleep in it, FYI islam is against racism and there's millions of Chinese Muslims who goes to mosques in China too :)

Most likely they would allow you to if not try to find a hotel or something
They can't reject you for being Chinese

Mosques are not sleeping tho but it's allowed to sleep in it for itikhaf etc