If employee needs to pay back to home country tax office for tax benefit in host country?

Normally employee's salary has been deducted for hypo tax. But this amount is not exactly amount, more or less. In my understanding, if the actual tax in host country larger than hypo tax, then employee or company will be charged. But if the actual tax in host country is smaller than hypo tax. I'd like to know whether employee needs to pay back to home country tax office for tax benefit in host country? Or just get this part of benefit from home country company.

Firstly I dont know if you realised you posted this in "Australia"

Secondly what is hypo tax?

In Australia any income you earned you pay tax on, in Australia.