Even though she thought that but she shook her head and said "No dear that's not possible!!!"
Even though she agreed to his all requests but this request is a little too much for herself.
Liam also know that she won't agree to this after all the idea is so perverted but it was not his intention.
He asked her because he wanted to implement it in the future.
He replied "I was asking you whether to do this or not mom! Don't worry if you are not comfortable with this idea then we won't do that."
Lilith sighed in relief because she didn't know what would she do if he force her to do that. As his 'qualified' mother she didn't wanted him to refuse but her son is thinks a lot of perverted things that in end she needs to refuse him.
Liam saw her sighing in relief.
Then he said "But mom I can satisfy you if you are feeling any lust."
Lilith shook her head and said "T-that no let's get the milk out from my breasts."