Is this unreasonable to ask?

My boyfriend & I are going to house sit his mums house for 1 month whilst she’s away to look after he cat etc.

We pay my parents ‘rent’ which we’ve been told is just for bills etc. As we won’t be there for a month and won’t be using any gas & electicity I thought it worth asking if we could pay a reduced rent like half??

I know if my dad was an actual landlord the real world doesn’t work like that but we’ve already rented a flat so we know that’s the case. We moved back in to save money- mt friends all think I should ask but I’m just worried about my dads reaction but at the same time don’t want to be paying full rent if we aren’t using any electric etc

Wont get if you dont try asking. Nothing to lose and I'm sure you father of all people would be reasonable to his child.