I was watching 'Merlin, the poisoned chalice' and suddenly thought of a manga I read a while back.

The main character was female and I can't remember anything about her, maybe she was born into a position of high standing?
The main male character had been used to test poisons since he was very young and I think maybe he even became poisonous to the touch.
Also I think maybe he was at her side when she was young but then left her service and at the beginning of the manga returns and somehow comes into her service again.
My memory is kinda patchy...

Ring any bells?

must be Apothecarius Argentum

Wahoo, that was super fast thank you ^^