bls where the MC is a butler/servant type character

butler
The Servant / Employer
On the Bit
Like A Fever Dream
master x secretary
should I write you a love letter instead?
Orca Mansion

Royal Servant, if you’re interested in a slight oldie

https://www.mangago.zone/read-manga/kashikomarimashita_destiny/

Second couple Alpha/Beta servants. One of my all-time favorites.

Mania