Multiple serial number per 1 EA

Dear Team,

This is a very odd requirement from my customer.

He want to post more than 1 serial number for 1 EA while doing GR against Purchase order.

Example :

One material say X, is being procured for 1 EA. and it is serial managed.

While doing GR of the PO, system activate tab of serial number in MIGO and only one entry is open. As per standard SAP and logic it is correct.

I conveyed him the same but he is not agreed.

My customer is telling that "This material consists 1-2 other components which are also serial number managed and they want transparency of those components as well."

Can someone guide on this? is there any other way like procurement BOM, etc?

Thanks