I read this some years ago. Its about a boy who died(?) and was reincarnated to another world where he became an OP butler. Fast forward to some years, the boy's childhood friend was summoned as a hero and they met again. Is this still being translated?
https://www.novelupdates.com/series/souen-no-historia/ prolly this one it seems web novel stopped being updated and it has a light novel, which is not being translated? not sure how far you've read though so there might be more content for you to read still